Documentation/config-gerrit.txt

= Gerrit Code Review - Configuration

== File `etc/gerrit.config`

The optional file `'$site_path'/etc/gerrit.config` is a Git-style
config file that controls many host specific settings for Gerrit.

[NOTE]
The contents of the `etc/gerrit.config` file are cached at startup
by Gerrit.  If you modify any properties in this file, Gerrit needs
to be restarted before it will use the new values.

Sample `etc/gerrit.config`:
----
[core]
  packedGitLimit = 200 m

[cache]
  directory = /var/cache/gerrit2
----

[[accounts]]
=== Section accounts

[[accounts.visibility]]accounts.visibility::
+
Controls visibility of other users' dashboard pages and
completion suggestions to web users.
+
If `ALL`, all users are visible to all other users, even
anonymous users.
+
If `SAME_GROUP`, only users who are also members of a group the
current user is a member of are visible.
+
If `VISIBLE_GROUP`, only users who are members of at least one group
that is visible to the current user are visible.
+
If `NONE`, no users other than the current user are visible.
+
Default is `ALL`.

[[addreviewer]]
=== Section addreviewer

[[addreviewer.maxWithoutConfirmation]]addreviewer.maxWithoutConfirmation::
+
The maximum number of reviewers a user can add at once by adding a
group as reviewer without being asked to confirm the operation.
+
If set to 0, the user will never be asked to confirm adding a group
as reviewer.
+
Default is 10.
+
This setting only applies for adding reviewers in the Gerrit WebUI,
but is ignored when adding reviewers with the
link:cmd-set-reviewers.html[set-reviewers] command.

[[addreviewer.maxAllowed]]addreviewer.maxAllowed::
+
The maximum number of reviewers a user can add at once by adding a
group as reviewer.
+
If set to 0, there is no limit for the number of reviewers that can
be added at once by adding a group as reviewer.
+
Default is 20.

[[auth]]
=== Section auth

See also link:config-sso.html[SSO configuration].

[[auth.type]]auth.type::
+
Type of user authentication employed by Gerrit.  The supported
values are:
+
* `OpenID`
+
The default setting.  Gerrit uses any valid OpenID
provider chosen by the end-user.  For more information see
http://openid.net/[openid.net].
+
* `OpenID_SSO`
+
Supports OpenID from a single provider.  There is no registration
link, and the "Sign In" link sends the user directly to the provider's
SSO entry point.
+
* `HTTP`
+
Gerrit relies upon data presented in the HTTP request.  This includes
HTTP basic authentication, or some types of commercial single-sign-on
solutions.  With this setting enabled the authentication must
take place in the web server or servlet container, and not from
within Gerrit.
+
* `HTTP_LDAP`
+
Exactly like `HTTP` (above), but additionally Gerrit pre-populates
a user's full name and email address based on information obtained
from the user's account object in LDAP.  The user's group membership
is also pulled from LDAP, making any LDAP groups that a user is a
member of available as groups in Gerrit.
+
* `CLIENT_SSL_CERT_LDAP`
+
This authentication type is actually kind of SSO. Gerrit will configure
Jetty's SSL channel to request the client's SSL certificate. For this
authentication to work a Gerrit administrator has to import the root
certificate of the trust chain used to issue the client's certificate
into the <review-site>/etc/keystore.
After the authentication is done Gerrit will obtain basic user
registration (name and email) from LDAP, and some group memberships.
Therefore, the "_LDAP" suffix in the name of this authentication type.
This authentication type can only be used under hosted daemon mode, and
the httpd.listenUrl must use https:// as the protocol.
Optionally, certificate revocation list file can be used
at <review-site>/etc/crl.pem. For details, see httpd.sslCrl.
+
* `LDAP`
+
Gerrit prompts the user to enter a username and a password, which
it then verifies by performing a simple bind against the configured
<<ldap.server,ldap.server>>.  In this configuration the web server
is not involved in the user authentication process.
+
The actual username used in the LDAP simple bind request is the
account's full DN, which is discovered by first querying the
directory using either an anonymous request, or the configured
<<ldap.username,ldap.username>> identity. Gerrit can also use kerberos if
<<ldap.authentication,ldap.authentication>> is set to `GSSAPI`.

* `LDAP_BIND`
+
Gerrit prompts the user to enter a username and a password, which
it then verifies by performing a simple bind against the configured
<<ldap.server,ldap.server>>.  In this configuration the web server
is not involved in the user authentication process.
+
Unlike `LDAP` above, the username used to perform the LDAP simple bind
request is the exact string supplied in the dialog by the user.
The configured <<ldap.username,ldap.username>> identity is not used to obtain
account information.
+
* `DEVELOPMENT_BECOME_ANY_ACCOUNT`
+
*DO NOT USE*.  Only for use in a development environment.
+
When this is the configured authentication method a hyperlink titled
`Become` appears in the top right corner of the page, taking the
user to a form where they can enter the username of any existing
user account, and immediately login as that account, without any
authentication taking place.  This form of authentication is only
useful for the GWT hosted mode shell, where OpenID authentication
redirects might be risky to the developer's host computer, and HTTP
authentication is not possible.

+
By default, OpenID.

[[auth.allowedOpenID]]auth.allowedOpenID::
+
List of permitted OpenID providers.  A user may only authenticate
with an OpenID that matches this list.  Only used if `auth.type`
is set to `OpenID` (the default).
+
Patterns may be either a
link:http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html[standard
Java regular expression (java.util.regex)] (start with `^` and
end with `$`) or be a simple prefix (any other string).
+
By default, the list contains two values, `http://` and `https://`,
allowing users to authenticate with any OpenID provider.

[[auth.trustedOpenID]]auth.trustedOpenID::
+
List of trusted OpenID providers.  Only used if `auth.type` is
set to `OpenID` (the default).
+
In order for a user to take advantage of permissions beyond those
granted to the `Anonymous Users` and `Registered Users` groups,
the user account must only have OpenIDs which match at least one
pattern from this list.
+
Patterns may be either a
link:http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html[standard
Java regular expression (java.util.regex)] (start with `^` and
end with `$`) or be a simple prefix (any other string).
+
By default, the list contains two values, `http://` and `https://`,
allowing Gerrit to trust any OpenID it receives.

[[auth.openIdDomain]]auth.openIdDomain::
+
List of allowed OpenID email address domains. Only used if
`auth.type` is set to `OPENID` or `OPENID_SSO`.
+
Domain is case insensitive and must be in the same form as it
appears in the email address, for example, "example.com".
+
By default, any domain is accepted.

[[auth.maxOpenIdSessionAge]]auth.maxOpenIdSessionAge::
+
Time in seconds before an OpenID provider must force the user
to authenticate themselves again before authentication to this
Gerrit server.  Currently this is only a polite request, and users
coming from providers that don't support the PAPE extension will
be accepted anyway.  In the future it may be enforced, rejecting
users coming from providers that don't honor the max session age.
+
If set to 0, the provider will always force the user to authenticate
(e.g. supply their password).  Values should use common unit suffixes
to express their setting:
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days
* w, week, weeks (`1 week` is treated as `7 days`)
* mon, month, months (`1 month` is treated as `30 days`)
* y, year, years (`1 year` is treated as `365 days`)

+
Default is -1, permitting infinite time between authentications.

[[auth.maxRegisterEmailTokenAge]]auth.maxRegisterEmailTokenAge::
+
Time in seconds before an email verification token sent to a user in
order to validate their email address expires.
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days
* w, week, weeks (`1 week` is treated as `7 days`)
* mon, month, months (`1 month` is treated as `30 days`)
* y, year, years (`1 year` is treated as `365 days`)

+
Default is 12 hours.

[[auth.openIdSsoUrl]]auth.openIdSsoUrl::
+
The SSO entry point URL.  Only used if `auth.type` is set to
`OpenID_SSO`.
+
The "Sign In" link will send users directly to this URL.

[[auth.httpHeader]]auth.httpHeader::
+
HTTP header to trust the username from, or unset to select HTTP basic
or digest authentication.  Only used if `auth.type` is set to `HTTP`.

[[auth.httpDisplaynameHeader]]auth.httpDisplaynameHeader::
+
HTTP header to retrieve the user's display name from.  Only used if `auth.type`
is set to `HTTP`.
+
If set, Gerrit trusts and enforces the user's full name using the HTTP header
and disables the ability to manually modify the user's full name
from the contact information page.

[[auth.httpEmailHeader]]auth.httpEmailHeader::
+
HTTP header to retrieve the user's e-mail from.  Only used if `auth.type`
is set to `HTTP`.
+
If set, Gerrit trusts and enforces the user's e-mail using the HTTP header
and disables the ability to manually modify or register other e-mails
from the contact information page.

[[auth.loginUrl]]auth.loginUrl::
+
URL to redirect a browser to after the end-user has clicked on the
login link in the upper right corner. Only used if `auth.type` is set
to `HTTP` or `HTTP_LDAP`.
Organizations using an enterprise single-sign-on solution may want to
redirect the browser to the SSO product's sign-in page for completing the
login process and validate their credentials.
+
If set, Gerrit allows anonymous access until the end-user performs the login
and provides a trusted identity through the HTTP header.
If not set, Gerrit requires the HTTP header with a trusted identity
and returns the error page 'LoginRedirect.html' if such a header is not
present.

[[auth.loginText]]auth.loginText::
+
Text displayed in the loginUrl link. Only used if `auth.loginUrl` is set.
+
If not set, the "Sign In" text is used.

[[auth.registerPageUrl]]auth.registerPageUrl::
+
URL of the registration page to use when a new user logs in to Gerrit for
the first time. Used only when `auth.type` is set to `HTTP`.
+
If not set, the standard Gerrit registration page `/#/register/` is displayed.

[[auth.logoutUrl]]auth.logoutUrl::
+
URL to redirect a browser to after the end-user has clicked on the
"Sign Out" link in the upper right corner.  Organizations using an
enterprise single-sign-on solution may want to redirect the browser
to the SSO product's sign-out page.
+
If not set, the redirect returns to the list of all open changes.

[[auth.registerUrl]]auth.registerUrl::
+
Target for the "Register" link in the upper right corner.  Used only
when `auth.type` is `LDAP`.
+
If not set, no "Register" link is displayed.

[[auth.registerText]]auth.registerText::
+
Text for the "Register" link in the upper right corner.  Used only
when `auth.type` is `LDAP`.
+
If not set, defaults to "Register".

[[auth.editFullNameUrl]]auth.editFullNameUrl::
+
Target for the "Edit" button when the user is allowed to edit their
full name.

[[auth.httpPasswordUrl]]auth.httpPasswordUrl::
+
Target for the "Obtain Password" link.  Used only when `auth.type` is
`LDAP`, `LDAP_BIND` or `CUSTOM_EXTENSION`.

[[auth.switchAccountUrl]]auth.switchAccountUrl::
+
URL to switch user identities and login as a different account than
the currently active account.  This is disabled by default except when
`auth.type` is `OPENID` and `DEVELOPMENT_BECOME_ANY_ACCOUNT`.  If set
the "Switch Account" link is displayed next to "Sign Out".
+
When `auth.type` does not normally enable this URL administrators may
set this to `login/` or `$canonicalWebUrl/login`, allowing users to
begin a new web session.

[[auth.cookiePath]]auth.cookiePath::
+
Sets "path" attribute of the authentication cookie.
+
If not set, HTTP request's path is used.

[[auth.cookieSecure]]auth.cookieSecure::
+
Sets "secure" flag of the authentication cookie.  If true, cookies
will be transmitted only over HTTPS protocol.
+
By default, false.

[[auth.emailFormat]]auth.emailFormat::
+
Optional format string to construct user email addresses out of
user login names.  Only used if `auth.type` is `HTTP`, `HTTP_LDAP`
or `LDAP`.
+
This value can be set to a format string, where `{0}` is replaced
with the login name.  E.g. "\{0\}+gerrit@example.com" with a user
login name of "foo" will produce "foo+gerrit@example.com" during
the first time user "foo" registers.
+
If the site is using `HTTP_LDAP` or `LDAP`, using this option is
discouraged.  Setting `ldap.accountEmailAddress` and importing the
email address from the LDAP directory is generally preferred.

[[auth.contributorAgreements]]auth.contributorAgreements::
+
Controls whether or not the contributor agreement features are
enabled for the Gerrit site.  If enabled a user must complete a
contributor agreement before they can upload changes.
+
If enabled, the admin must also add one or more
link:config-cla.html[contributor-agreement sections]
in project.config and create agreement files under
`'$site_path'/static`, so users can actually complete one or
more agreements.
+
By default this is false (no agreements are used).
+
To enable the actual usage of contributor agreement the project
specific config option in the `project.config` must be set:
link:config-project-config.html[receive.requireContributorAgreement].

auth.allowGoogleAccountUpgrade::
+
Allows Google Account users to automatically update their Gerrit
account when/if their Google Account OpenID identity token changes.
Identity tokens can change if the server changes hostnames, or
for other reasons known only to Google.  The upgrade path works
by matching users by email address if the identity is not present,
and then changing the identity.
+
This setting also permits old Gerrit 1.x users to seamlessly upgrade
from Google Accounts on Google App Engine to OpenID authentication.
+
Having this enabled incurs an extra database query when Google
Account users register with the Gerrit server.
+
By default, unset/false.

[[auth.trustContainerAuth]]auth.trustContainerAuth::
+
If true then it is the responsibility of the container hosting
Gerrit to authenticate users. In this case Gerrit will blindly trust
the container.
+
This parameter only affects git over http traffic. If set to false
then Gerrit will do the authentication (using DIGEST authentication).
+
By default this is set to false.

[[auth.gitBasicAuth]]auth.gitBasicAuth::
+
If true then Git over HTTP and HTTP/S traffic is authenticated using
standard BasicAuth and credentials validated using the same auth
method configured for Gerrit Web UI.
+
This parameter only affects git over http traffic. If set to false
then Gerrit will authenticate through DIGEST authentication and
the randomly generated HTTP password in Gerrit DB.
+
By default this is set to false.

[[auth.userNameToLowerCase]]auth.userNameToLowerCase::
+
If set the username that is received to authenticate a git operation
is converted to lower case for looking up the user account in Gerrit.
+
By setting this parameter a case insensitive authentication for the
git operations can be achieved, if it is ensured that the usernames in
Gerrit (scheme `username`) are stored in lower case (e.g. if the
parameter link:#ldap.accountSshUserName[ldap.accountSshUserName] is
set to `${sAMAccountName.toLowerCase}`). It is important that for all
existing accounts this username is already in lower case. It is not
possible to convert the usernames of the existing accounts to lower
case because this would break the access to existing per-user
branches.
+
This parameter only affects git over http and git over SSH traffic.
+
By default this is set to false.

[[auth.enableRunAs]]auth.enableRunAs::
+
If true HTTP REST APIs will accept the `X-Gerrit-RunAs` HTTP request
header from any users granted the link:access-control.html#capability_runAs[Run As]
capability. The header and capability permit the authenticated user
to impersonate another account.
+
If false the feature is disabled and cannot be re-enabled without
editing gerrit.config and restarting the server.
+
Default is true.

[[cache]]
=== Section cache

[[cache.directory]]cache.directory::
+
Path to a local directory where Gerrit can write cached entities for
future lookup.  This local disk cache is used to retain potentially
expensive to compute information across restarts.  If the location
does not exist, Gerrit will try to create it.
+
If not absolute, the path is resolved relative to `$site_path`.
+
Default is unset, no disk cache.

[[cache.name.maxAge]]cache.<name>.maxAge::
+
Maximum age to keep an entry in the cache. Entries are removed from
the cache and refreshed from source data every maxAge interval.
Values should use common unit suffixes to express their setting:
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days
* w, week, weeks (`1 week` is treated as `7 days`)
* mon, month, months (`1 month` is treated as `30 days`)
* y, year, years (`1 year` is treated as `365 days`)

+
If a unit suffix is not specified, `seconds` is assumed.  If 0 is
supplied, the maximum age is infinite and items are never purged
except when the cache is full.
+
Default is `0`, meaning store forever with no expire, except:
+
* `"adv_bases"`: default is `10 minutes`
* `"ldap_groups"`: default is `1 hour`
* `"web_sessions"`: default is `12 hours`

[[cache.name.memoryLimit]]cache.<name>.memoryLimit::
+
The total cost of entries to retain in memory. The cost computation
varies by the cache. For most caches where the in-memory size of each
entry is relatively the same, memoryLimit is currently defined to be
the number of entries held by the cache (each entry costs 1).
+
For caches where the size of an entry can vary significantly between
individual entries (notably `"diff"`, `"diff_intraline"`), memoryLimit
is an approximation of the total number of bytes stored by the cache.
Larger entries that represent bigger patch sets or longer source files
will consume a bigger portion of the memoryLimit. For these caches the
memoryLimit should be set to roughly the amount of RAM (in bytes) the
administrator can dedicate to the cache.
+
Default is 1024 for most caches, except:
+
* `"adv_bases"`: default is `4096`
* `"diff"`: default is `10m` (10 MiB of memory)
* `"diff_intraline"`: default is `10m` (10 MiB of memory)
* `"plugin_resources"`: default is 2m (2 MiB of memory)

+
If set to 0 the cache is disabled. Entries are removed immediately
after being stored by the cache. This is primarily useful for testing.

[[cache.name.diskLimit]]cache.<name>.diskLimit::
+
Total size in bytes of the keys and values stored on disk. Caches that
have grown bigger than this size are scanned daily at 1 AM local
server time to trim the cache. Entries are removed in least recently
accessed order until the cache fits within this limit.  Caches may
grow larger than this during the day, as the size check is only
performed once every 24 hours.
+
Default is 128 MiB per cache.
+
If 0, disk storage for the cache is disabled.

==== [[cache_names]]Standard Caches

cache `"accounts"`::
+
Cache entries contain important details of an active user, including
their display name, preferences, known email addresses, and group
memberships.  Entry information is obtained from the following
database tables:
+
* `accounts`
+
* `account_group_members`
+
* `account_external_ids`

+
If direct updates are made to any of these database tables, this
cache should be flushed.

cache `"accounts_byemail"`::
+
Caches account identities keyed by email address, which is scanned
from the `account_external_ids` database table.  If updates are
made to this table, this cache should be flushed.

cache `"adv_bases"`::
+
Used only for push over smart HTTP when branch level access controls
are enabled.  The cache entry contains all commits that are available
for the client to use as potential delta bases.  Push over smart HTTP
requires two HTTP requests, and this cache tries to carry state from
the first request into the second to ensure it can complete.

cache `"changes"`::
+
The size of `memoryLimit` determines the number of projects for which
all changes will be cached. If the cache is set to 1024, this means all
changes for up to 1024 projects can be held in the cache.
+
Default value is 0 (disabled). It is disabled by default due to the fact
that change updates are not communicated between Gerrit servers. Hence
this cache should be disabled in an multi-master/multi-slave setup.
+
The cache should be flushed whenever the database changes table is modified
outside of Gerrit.

cache `"diff"`::
+
Each item caches the differences between two commits, at both the
directory and file levels.  Gerrit uses this cache to accelerate
the display of affected file names, as well as file contents.
+
Entries in this cache are relatively large, so memoryLimit is an
estimate in bytes of memory used. Administrators should try to target
cache.diff.memoryLimit to fit all changes users will view in a 1 or 2
day span.

cache `"diff_intraline"`::
+
Each item caches the intraline difference of one file, when compared
between two commits. Gerrit uses this cache to accelerate display of
intraline differences when viewing a file.
+
Entries in this cache are relatively large, so memoryLimit is an
estimate in bytes of memory used. Administrators should try to target
cache.diff.memoryLimit to fit all files users will view in a 1 or 2
day span.

cache `"git_tags"`::
+
If branch or reference level READ access controls are used, this
cache tracks which tags are reachable from the branch tips of a
repository.  Gerrit uses this information to determine the set
of tags that a client may access, derived from which tags are
part of the history of a visible branch.
+
The cache is persisted to disk across server restarts as it can
be expensive to compute (60 or more seconds for a large history
like the Linux kernel repository).

cache `"groups"`::
+
Caches the basic group information from the `account_groups` table,
including the group owner, name, and description.
+
Gerrit group membership obtained from the `account_group_members`
table is cached under the `"accounts"` cache, above.  External group
membership obtained from LDAP is cached under `"ldap_groups"`.

cache `"groups_byinclude"`::
+
Caches group inclusions in other groups.  If direct updates are made
to the `account_group_includes` table, this cache should be flushed.

cache `"ldap_groups"`::
+
Caches the LDAP groups that a user belongs to, if LDAP has been
configured on this server.  This cache should be configured with a
low maxAge setting, to ensure LDAP modifications are picked up in
a timely fashion.

cache `"ldap_groups_byinclude"`::
+
Caches the hierarchical structure of LDAP groups.

cache `"ldap_usernames"`::
+
Caches a mapping of LDAP username to Gerrit account identity.  The
cache automatically updates when a user first creates their account
within Gerrit, so the cache expire time is largely irrelevant.

cache `"permission_sort"`::
+
Caches the order in which access control sections must be applied to a
reference.  Sorting the sections can be expensive when regular
expressions are used, so this cache remembers the ordering for
each branch.

cache `"plugin_resources"`::
+
Caches formatted plugin resources, such as plugin documentation that
has been converted from Markdown to HTML. The memoryLimit refers to
the bytes of memory dedicated to storing the documentation.

cache `"projects"`::
+
Caches the project description records, from the `projects` table
in the database.  If a project record is updated or deleted, this
cache should be flushed.  Newly inserted projects do not require
a cache flush, as they will be read upon first reference.

cache `"sshkeys"`::
+
Caches unpacked versions of user SSH keys, so the internal SSH daemon
can match against them during authentication.  The unit of storage
is per-user, so 1024 items translates to 1024 unique user accounts.
As each individual user account may configure multiple SSH keys,
the total number of keys may be larger than the item count.
+
This cache is based off the `account_ssh_keys` table and the
`accounts.ssh_user_name` column in the database.  If either is
modified directly, this cache should be flushed.

cache `"web_sessions"`::
+
Tracks the live user sessions coming in over HTTP.  Flushing this
cache would cause all users to be signed out immediately, forcing
them to sign-in again.  To avoid breaking active users, this cache
is not flushed automatically by `gerrit flush-caches --all`, but
instead must be explicitly requested.
+
If no disk cache is configured (or `cache.web_sessions.diskLimit`
is set to 0) a server restart will force all users to sign-out,
and need to sign-in again after the restart, as the cache was
unable to persist the session information.  Enabling a disk cache
is strongly recommended.
+
Session storage is relatively inexpensive. The average entry in
this cache is approximately 346 bytes.

See also link:cmd-flush-caches.html[gerrit flush-caches].

==== [[cache_options]]Cache Options

[[cache.diff_intraline.maxIdleWorkers]]cache.diff_intraline.maxIdleWorkers::
+
Number of idle worker threads to maintain for the intraline difference
computations.  There is no upper bound on how many concurrent requests
can occur at once, if additional threads are started to handle a peak
load, only this many will remain idle afterwards.
+
Default is 1.5x number of available CPUs.

[[cache.diff_intraline.timeout]]cache.diff_intraline.timeout::
+
Maximum number of milliseconds to wait for intraline difference data
before giving up and disabling it for a particular file pair.  This is
a work around for an infinite loop bug in the intraline difference
implementation.
+
If computation takes longer than the timeout, the worker thread is
terminated, an error message is shown, and no intraline difference is
displayed for the file pair.
+
Values should use common unit suffixes to express their setting:
+
* ms, milliseconds
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours

+
If a unit suffix is not specified, `milliseconds` is assumed.
+
Default is 5 seconds.

[[cache.diff_intraline.enabled]]cache.diff_intraline.enabled::
+
Boolean to enable or disable the computation of intraline differences
when populating a diff cache entry.  This flag is provided primarily
as a backdoor to disable the intraline difference feature if
necessary.  To maintain backwards compatibility with prior versions,
this setting will fallback to `cache.diff.intraline` if not set in the
configuration.
+
Default is true, enabled.

[[cache.projects.checkFrequency]]cache.projects.checkFrequency::
+
How often project configuration should be checked for update from Git.
Gerrit Code Review caches project access rules and configuration in
memory, checking the refs/meta/config branch every checkFrequency
minutes to see if a new revision should be loaded and used for future
access. Values can be specified using standard time unit abbreviations
('ms', 'sec', 'min', etc.).
+
If set to 0, checks occur every time, which may slow down operations.
If set to 'disabled' or 'off', no check will ever be done.
Administrators may force the cache to flush with
link:cmd-flush-caches.html[gerrit flush-caches].
+
Default is 5 minutes.

[[change]]
=== Section change

[[change.largeChange]]change.largeChange::
+
Number of changed lines from which on a change is considered as a large
change. The number of changed lines of a change is the sum of the lines
that were inserted and deleted in the change.
+
The specified value is used to visualize the change sizes in the web UI
in change tables and user dashboards.
+
By default 500.

[[change.updateDelay]]change.updateDelay::
+
How often in seconds the web interface should poll for updates to the
currently open change.  The poller relies on the client's browser
cache to use If-Modified-Since and respect `304 Not Modified` HTTP
responses.  This allows for fast polls, often under 8 milliseconds.
+
With a configured 30 second delay a server with 4900 active users will
typically need to dedicate 1 CPU to the update check.  4900 users
divided by an average delay of 30 seconds is 163 requests arriving per
second.  If requests are served at ~6 ms response time, 1 CPU is
necessary to keep up with the update request traffic.  On a smaller
user base of 500 active users, the default 30 second delay is only 17
requests per second and requires ~10% CPU.
+
If 0 the update polling is disabled.
+
Default is 30 seconds.

[[change.allowDrafts]]change.allowDrafts::
+
Allow drafts workflow. If set to false, drafts cannot be created,
deleted or published.
+
Default is true.

[[changeMerge]]
=== Section changeMerge

[[changeMerge.checkFrequency]]changeMerge.checkFrequency::
+
How often the database should be rescanned for changes that have been
submitted but not merged due to transient errors. Values can be
specified using standard time unit abbreviations ('ms', 'sec', 'min',
etc.). Set to 0 to disable periodic rescanning, only scanning once on
master node startup.
+
Default is 300 seconds (5 minutes).

[[changeMerge.threadPoolSize]]changeMerge.threadPoolSize::
+
Maximum size of the thread pool in which the mergeability flag of open
changes is updated.
+
Default is 1.

[[commentlink]]
=== Section commentlink

Comment links are find/replace strings applied to change descriptions,
patch comments, in-line code comments and approval category value descriptions
to turn set strings into hyperlinks.  One common use is for linking to
bug-tracking systems.

In the following example configuration the 'changeid' comment link
will match typical Gerrit Change-Id values and create a hyperlink
to changes which reference it.  The second configuration 'bugzilla'
will hyperlink terms such as 'bug 42' to an external bug tracker,
supplying the argument record number '42' for display.  The third
configuration 'tracker' uses raw HTML to more precisely control
how the replacement is displayed to the user.

----
[commentlink "changeid"]
  match = (I[0-9a-f]{8,40})
  link = "#q,$1"

[commentlink "bugzilla"]
  match = "(bug\\s+#?)(\\d+)"
  link = http://bugs.example.com/show_bug.cgi?id=$2

[commentlink "tracker"]
  match = ([Bb]ug:\\s+)(\\d+)
  html = $1<a href=\"http://trak.example.com/$2\">$2</a>
----

Comment links can also be specified in `project.config` and sections in
children override those in parents. The only restriction is that to
avoid injecting arbitrary user-supplied HTML in the page, comment links
defined in `project.config` may only supply `link`, not `html`.

[[commentlink.name.match]]commentlink.<name>.match::
+
A JavaScript regular expression to match positions to be replaced
with a hyperlink.  Subexpressions of the matched string can be
stored using groups and accessed with `$'n'` syntax, where 'n'
is the group number, starting from 1.
+
The configuration file parser eats one level of backslashes, so the
character class `\s` requires `\\s` in the configuration file.  The
parser also terminates the line at the first `#`, so a match
expression containing # must be wrapped in double quotes.
+
To match case insensitive strings, a character class with both the
upper and lower case character for each position must be used.  For
example, to match the string `bug` in a case insensitive way the match
pattern `[bB][uU][gG]` needs to be used.
+
A common pattern to match is `bug\\s+(\\d+)`.

[[commentlink.name.link]]commentlink.<name>.link::
+
The URL to direct the user to whenever the regular expression is
matched.  Groups in the match expression may be accessed as `$'n'`.
+
The link property is used only when the html property is not present.

[[commentlink.name.html]]commentlink.<name>.html::
+
HTML to replace the entire matched string with.  If present,
this property overrides the link property above.  Groups in the
match expression may be accessed as `$'n'`.
+
The configuration file eats double quotes, so escaping them as
`\"` is necessary to protect them from the parser.

[[commentlink.name.enabled]]commentlink.<name>.enabled::
+
Whether the comment link is enabled. A child project may override a
section in a parent or the site-wide config that is disabled by
specifying `enabled = true`.
+
Disabling sections in `gerrit.config` can be used by site administrators
to create a library of comment links with `html` set that are not
user-supplied and thus can be verified to be XSS-free, but are only
enabled for a subset of projects.
+
By default, true.
+
Note that the names and contents of disabled sections are visible even
to anonymous users via the
link:rest-api-projects.html#get-config[REST API].


[[contactstore]]
=== Section contactstore

[[contactstore.url]]contactstore.url::
+
URL of the web based contact store Gerrit will send any offline
contact information to when it collects the data from users as part
of a contributor agreement.
+
See link:config-contact.html[Contact Information].

[[contactstore.appsec]]contactstore.appsec::
+
Shared secret of the web based contact store.


[[container]]
=== Section container

These settings are applied only if Gerrit is started as the container
process through Gerrit's 'gerrit.sh' rc.d compatible wrapper script.

[[container.heapLimit]]container.heapLimit::
+
Maximum heap size of the Java process running Gerrit, in bytes.
This property is translated into the '-Xmx' flag for the JVM.
+
Default is platform and JVM specific.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[container.javaHome]]container.javaHome::
+
Path of the JRE/JDK installation to run Gerrit with.  If not set, the
Gerrit startup script will attempt to search your system and guess
a suitable JRE.  Overrides the environment variable 'JAVA_HOME'.

[[container.javaOptions]]container.javaOptions::
+
Additional options to pass along to the Java runtime.  If multiple
values are configured, they are passed in order on the command line,
separated by spaces.  These options are appended onto 'JAVA_OPTIONS'.

For example, it is possible to overwrite Gerrit's default log4j
configuration:

----
  javaOptions = -Dlog4j.configuration=file:///home/gerrit/site/etc/log4j.properties
----

[[container.slave]]container.slave::
+
Used on Gerrit slave installations. If set to true the Gerrit JVM is
called with the '--slave' switch, enabling slave mode. If no value is
set (or any other value), Gerrit defaults to master mode.

[[container.user]]container.user::
+
Login name (or UID) of the operating system user the Gerrit JVM
will execute as.  If not set, defaults to the user who launched
the 'gerrit.sh' wrapper script.

[[container.war]]container.war::
+
Path of the JAR file to start daemon execution with.  This should
be the path of the local 'gerrit.war' archive.  Overrides the
environment variable 'GERRIT_WAR'.
+
If not set, defaults to '$site_path/bin/gerrit.war', or to
'$HOME/gerrit.war'.


[[core]]
=== Section core

[[core.packedGitWindowSize]]core.packedGitWindowSize::
+
Number of bytes of a pack file to load into memory in a single
read operation.  This is the "page size" of the JGit buffer cache,
used for all pack access operations.  All disk IO occurs as single
window reads.  Setting this too large may cause the process to load
more data than is required; setting this too small may increase
the frequency of `read()` system calls.
+
Default on JGit is 8 KiB on all platforms.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[core.packedGitLimit]]core.packedGitLimit::
+
Maximum number of bytes to load and cache in memory from pack files.
If JGit needs to access more than this many bytes it will unload less
frequently used windows to reclaim memory space within the process.
As this buffer must be shared with the rest of the JVM heap, it
should be a fraction of the total memory available.
+
Default on JGit is 10 MiB on all platforms.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[core.deltaBaseCaseLimit]]core.deltaBaseCacheLimit::
+
Maximum number of bytes to reserve for caching base objects
that multiple deltafied objects reference.  By storing the entire
decompressed base object in a cache Git is able to avoid unpacking
and decompressing frequently used base objects multiple times.
+
Default on JGit is 10 MiB on all platforms.  You probably do not
need to adjust this value.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[core.packedGitOpenFiles]]core.packedGitOpenFiles::
+
Maximum number of pack files to have open at once.  A pack file
must be opened in order for any of its data to be available in
a cached window.
+
If you increase this to a larger setting you may need to also adjust
the ulimit on file descriptors for the host JVM, as Gerrit needs
additional file descriptors available for network sockets and other
repository data manipulation.
+
Default on JGit is 128 file descriptors on all platforms.

[[core.streamFileThreshold]]core.streamFileThreshold::
+
Largest object size, in bytes, that JGit will allocate as a
contiguous byte array.  Any file revision larger than this threshold
will have to be streamed, typically requiring the use of temporary
files under '$GIT_DIR/objects' to implement pseudo-random access
during delta decompression.
+
Servers with very high traffic should set this to be larger than
the size of their common big files.  For example a server managing
the Android platform typically has to deal with ~10-12 MiB XML
files, so `15 m` would be a reasonable setting in that environment.
Setting this too high may cause the JVM to run out of heap space
when handling very big binary files, such as device firmware or
CD-ROM ISO images.
+
Default is 50 MiB on all platforms.  Prior to Gerrit 2.1.6,
this value was effectively 2047 MiB.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[core.packedGitMmap]]core.packedGitMmap::
+
When true, JGit will use `mmap()` rather than `malloc()+read()`
to load data from pack files.  The use of mmap can be problematic
on some JVMs as the garbage collector must deduce that a memory
mapped segment is no longer in use before a call to `munmap()`
can be made by the JVM native code.
+
In server applications (such as Gerrit) that need to access many
pack files, setting this to true risks artificially running out
of virtual address space, as the garbage collector cannot reclaim
unused mapped spaces fast enough.
+
Default on JGit is false. Although potentially slower, it yields
much more predictable behavior.

[[core.asyncLoggingBufferSize]]core.asyncLoggingBufferSize::
+
Size of the buffer to store logging events for asynchronous logging.
Putting a larger value can protect threads from stalling when the
AsyncAppender threads are not fast enough to consume the logging events
from the buffer. It also protects from loosing log entries in this case.
+
Default is 64 entries.

[[core.useRecursiveMerge]]core.useRecursiveMerge::
+
Use JGit's new, experimental recursive merger for three-way merges.
This only affects projects configured to automatically resolve
conflicts.
+
Default is false, but in a future release may default to true.

[[database]]
=== Section database

The database section configures where Gerrit stores its metadata
records about user accounts and change reviews.

----
[database]
  type = POSTGRESQL
  hostname = localhost
  database = reviewdb
  username = gerrit2
  password = s3kr3t
----

[[database.type]]database.type::
+
Type of database server to connect to.  If set this value will be
used to automatically create correct database.driver and database.url
values to open the connection.
+
* `POSTGRESQL`
+
Connect to a PostgreSQL database server.
+
* `H2`
+
Connect to a local embedded H2 database.
+
* `MYSQL`
+
Connect to a MySQL database server.
+
* `JDBC`
+
Connect using a JDBC driver class name and URL.

+
If not specified, database.driver and database.url are used as-is,
and if they are also not specified, defaults to H2.

[[database.hostname]]database.hostname::
+
Hostname of the database server.  Defaults to 'localhost'.

[[database.port]]database.port::
+
Port number of the database server.  Defaults to the default port
of the server named by database.type.

[[database.database]]database.database::
+
For POSTGRESQL or MYSQL, the name of the database on the server.
+
For H2, this is the path to the database, and if not absolute is
relative to `'$site_path'`.

[[database.username]]database.username::
+
Username to connect to the database server as.

[[database.password]]database.password::
+
Password to authenticate to the database server with.

[[database.driver]]database.driver::
+
Name of the JDBC driver class to connect to the database with.
Setting this usually isn't necessary as it can be derived from
database.type or database.url for any supported database.

[[database.url]]database.url::
+
'jdbc:' URL for the database.  Setting this variable usually
isn't necessary as it can be constructed from the all of the
above properties.

[[database.connectionPool]]database.connectionPool::
+
If true, use connection pooling for database connections. Otherwise, a
new database connection is opened for each request.
+
Default is false for MySQL, and true for other database backends.

[[database.poolLimit]]database.poolLimit::
+
Maximum number of open database connections.  If the server needs
more than this number, request processing threads will wait up
to <<database.poolMaxWait, poolMaxWait>> seconds for a
connection to be released before they abort with an exception.
This limit must be several units higher than the total number of
httpd and sshd threads as some request processing code paths may
need multiple connections.
+
Default is 8.
+
This setting only applies if
<<database.connectionPool,database.connectionPool>> is true.

[[database.poolMinIdle]]database.poolMinIdle::
+
Minimum number of connections to keep idle in the pool.
Default is 4.
+
This setting only applies if
<<database.connectionPool,database.connectionPool>> is true.

[[database.poolMaxIdle]]database.poolMaxIdle::
+
Maximum number of connections to keep idle in the pool.  If there
are more idle connections, connections will be closed instead of
being returned back to the pool.
Default is 4.
+
This setting only applies if
<<database.connectionPool,database.connectionPool>> is true.

[[database.poolMaxWait]]database.poolMaxWait::
+
Maximum amount of time a request processing thread will wait to
acquire a database connection from the pool.  If no connection is
released within this time period, the processing thread will abort
its current operations and return an error to the client.
Values should use common unit suffixes to express their setting:
+
* ms, milliseconds
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours

+
If a unit suffix is not specified, `milliseconds` is assumed.
+
Default is `30 seconds`.
+
This setting only applies if
<<database.connectionPool,database.connectionPool>> is true.

[[database.dataSourceInterceptorClass]]database.dataSourceInterceptorClass::

Class that implements DataSourceInterceptor interface to monitor SQL activity.
This class must have default constructor and be available on Gerrit's bootstrap
classpath, e. g. in `$gerrit_site/lib` directory. Example implementation of
SQL monitoring can be found in javamelody-plugin.

[[download]]
=== Section download

----
[download]
  command = checkout
  command = cherry_pick
  command = pull
  command = format_patch
  scheme = ssh
  scheme = http
  scheme = anon_http
  scheme = anon_git
  scheme = repo_download
----

The download section configures the allowed download methods.

[[download.command]]download.command::
+
Commands that should be offered to download changes.
+
Multiple commands are supported:
+
* `checkout`
+
Command to fetch and checkout the patch set.
+
* `cherry_pick`
+
Command to fetch the patch set and to cherry-pick it onto the current
commit.
+
* `pull`
+
Command to pull the patch set.
+
* `format_patch`
+
Command to fetch the patch set and to feed it into the `format-patch`
command.

+
If `download.command` is not specified, all download commands are
offered.

[[download.scheme]]download.scheme::
+
Schemes that should be used to download changes.
+
Multiple schemes are supported:
+
* `http`
+
Authenticated HTTP download is allowed.
+
* `ssh`
+
Authenticated SSH download is allowed.
+
* `anon_http`
+
Anonymous HTTP download is allowed.
+
* `anon_git`
+
Anonymous Git download is allowed.  This is not default, it is also
necessary to set <<gerrit.canonicalGitUrl,gerrit.canonicalGitUrl>>
variable.
+
* `repo_download`
+
Gerrit advertises patch set downloads with the `repo download`
command, assuming that all projects managed by this instance are
generally worked on with the repo multi-repository tool.  This is
not default, as not all instances will deploy repo.

+
If `download.scheme` is not specified, SSH, HTTP and Anonymous HTTP
downloads are allowed.

[[gerrit]]
=== Section gerrit

[[gerrit.basePath]]gerrit.basePath::
+
Local filesystem directory holding all Git repositories that
Gerrit knows about and can process changes for.  A project
entity in Gerrit maps to a local Git repository by creating
the path string `"${basePath}/${project_name}.git"`.
+
If relative, the path is resolved relative to `'$site_path'`.

[[gerrit.allProjects]]gerrit.allProjects::
+
Name of the permissions-only project defining global server
access controls and settings. These are inherited into every
other project managed by the running server. The name is
relative to `gerrit.basePath`.
+
Defaults to `All-Projects` if not set.

[[gerrit.canonicalWebUrl]]gerrit.canonicalWebUrl::
+
The default URL for Gerrit to be accessed through.
+
Typically this would be set to "http://review.example.com/" or
"http://example.com/gerrit/" so Gerrit can output links that point
back to itself.
+
Setting this is highly recommended, as its necessary for the upload
code invoked by "git push" or "repo upload" to output hyperlinks
to the newly uploaded changes.

[[gerrit.canonicalGitUrl]]gerrit.canonicalGitUrl::
+
Optional base URL for repositories available over the anonymous git
protocol.  For example, set this to `git://mirror.example.com/base/`
to have Gerrit display patch set download URLs in the UI.  Gerrit
automatically appends the project name onto the end of the URL.
+
By default unset, as the git daemon must be configured externally
by the system administrator, and might not even be running on the
same host as Gerrit.

[[gerrit.installCommitMsgHookCommand]]gerrit.installCommitMsgHookCommand::
+
Optional command to install the `commit-msg` hook. Typically of the
form:
----
fetch-cmd some://url/to/commit-msg .git/hooks/commit-msg ; chmod +x .git/hooks/commit-msg
----

+
By default unset; falls back to using scp from the canonical SSH host,
or curl from the canonical HTTP URL for the server.  Only necessary if a
proxy or other server/network configuration prevents clients from
fetching from the default location.

[[gerrit.gitHttpUrl]]gerrit.gitHttpUrl::
+
Optional base URL for repositories available over the HTTP
protocol.  For example, set this to `http://mirror.example.com/base/`
to have Gerrit display URLs from this server, rather than itself.
+
By default unset, as the HTTP daemon must be configured externally
by the system administrator, and might not even be running on the
same host as Gerrit.

[[gerrit.reportBugUrl]]gerrit.reportBugUrl::
+
URL to direct users to when they need to report a bug about the
Gerrit service. By default this links to the upstream Gerrit
Code Review's own bug tracker but could be directed to the system
administrator's ticket queue.

[[gerrit.reportBugText]]gerrit.reportBugText::
+
Text to be displayed in the link to the bug report URL.
+
Defaults to "Report Bug".

[[gerrit.changeScreen]]gerrit.changeScreen::
+
Default change screen UI to direct users to. Valid values are
`OLD_UI` and `CHANGE_SCREEN2`. Default is `CHANGE_SCREEN2`.

[[gitweb]]
=== Section gitweb

Gerrit can forward requests to either an internally managed gitweb
(which allows Gerrit to enforce some access controls), or to an
externally managed gitweb (where the web server manages access).
See also link:config-gitweb.html[Gitweb Integration].

[[gitweb.cgi]]gitweb.cgi::
+
Path to the locally installed `gitweb.cgi` executable.  This CGI will
be called by Gerrit Code Review when the URL `/gitweb` is accessed.
Project level access controls are enforced prior to calling the CGI.
+
Defaults to `/usr/lib/cgi-bin/gitweb.cgi` if gitweb.url is not set.

[[gitweb.url]]gitweb.url::
+
Optional URL of an affiliated gitweb service.  Defines the
web location where a `gitweb.cgi` is installed to browse
gerrit.basePath and the repositories it contains.
+
Gerrit appends any necessary query arguments onto the end of this URL.
For example, "?p=$project.git;h=$commit".

[[gitweb.type]]gitweb.type::
+
Optional type of affiliated gitweb service. This allows using
alternatives to gitweb, such as cgit. If set to disabled there
is no gitweb hyperlinking support.
+
Valid values are `gitweb`, `cgit`, `disabled` or `custom`.

[[gitweb.revision]]gitweb.revision::
+
Optional pattern to use for constructing the gitweb URL when pointing
at a specific commit when `custom` is used above.
+
Valid replacements are `${project}` for the project name in Gerrit
and `${commit}` for the SHA1 hash for the commit.

[[gitweb.project]]gitweb.project::
+
Optional pattern to use for constructing the gitweb URL when pointing
at a specific project when `custom` is used above.
+
Valid replacements are `${project}` for the project name in Gerrit.

[[gitweb.branch]]gitweb.branch::
+
Optional pattern to use for constructing the gitweb URL when pointing
at a specific branch when `custom` is used above.
+
Valid replacements are `${project}` for the project name in Gerrit
and `${branch}` for the name of the branch.

[[gitweb.roottree]]gitweb.roottree::
+
Optional pattern to use for constructing the gitweb URL when pointing
at the contents of the root tree in a specific commit when `custom` is
used above.
+
Valid replacements are `${project}` for the project name in Gerrit
and `${commit}` for the SHA1 hash for the commit.

[[gitweb.file]]gitweb.file::
+
Optional pattern to use for constructing the gitweb URL when pointing
at the contents of a file in a specific commit when `custom` is used
above.
+
Valid replacements are `${project}` for the project name in Gerrit,
`${file}` for the file name and `${commit}` for the SHA1 hash for
the commit.

[[gitweb.filehistory]]gitweb.filehistory::
+
Optional pattern to use for constructing the gitweb URL when pointing
at the history of a file in a specific branch when `custom` is used
above.
+
Valid replacements are `${project}` for the project name in Gerrit,
`${file}` for the file name and `${branch}` for the name of the
branch.

[[gitweb.linkname]]gitweb.linkname::
+
Optional setting for modifying the link name presented to the user
in the Gerrit web-UI.
+
Default linkname for custom type is "gitweb".

[[gitweb.pathSeparator]]gitweb.pathSeparator::
+
Optional character to substitute the standard path separator (slash) in
project names and branch names.
+
By default, Gerrit will use hexadecimal encoding for slashes in project and
branch names. Some web servers, such as Tomcat, reject this hexadecimal
encoding in the URL.
+
Some alternative gitweb services, such as link:http://gitblit.com[Gitblit],
allow using an alternative path separator character. In Gitblit, this can be
configured through the property link:http://gitblit.com/properties.html[web.forwardSlashCharacter].
In Gerrit, the alternative path separator can be configured correspondingly
using the property 'gitweb.pathSeparator'.
+
Valid values are the characters '*', '(' and ')'.

[[gitweb.linkDrafts]]gitweb.urlEncode::
+
Whether or not Gerrit should encode the generated viewer URL.
+
Gerrit composes the viewer URL using information about the project, branch, file
or commit of the target object to be displayed. Typically viewers such as CGit
and GitWeb do need those parts to be encoded, including the '/' in project's name,
for being correctly parsed.
However other viewers could instead require an unencoded URL (e.g. GitHub web
based viewer)
+
Valid values are "true" and "false," default is "true."

[[gitweb.linkDrafts]]gitweb.linkDrafts::
+
Whether or not Gerrit should provide links to gitweb on draft patch sets.
+
By default, Gerrit will show links to gitweb on all patch sets. If gitweb
only allows publicly viewable references, set this to false to remove
the links to draft patch sets from the change review screen.
+
Valid values are "true" and "false," default is "true".

[[groups]]
=== Section groups

[[groups.newGroupsVisibleToAll]]groups.newGroupsVisibleToAll::
+
Controls whether newly created groups should be by default visible to
all registered users.
+
By default, false.

[[hooks]]
=== Section hooks

See also link:config-hooks.html[Hooks].

[[hooks.path]]hooks.path::
+
Optional path to hooks, if not specified then `'$site_path'/hooks` will be used.

[[hooks.patchsetCreatedHook]]hooks.patchsetCreatedHook::
+
Optional filename for the patchset created hook, if not specified then
`patchset-created` will be used.

[[hooks.draftPublishedHook]]hooks.draftPublishedHook::
+
Optional filename for the draft published hook, if not specified then
`draft-published` will be used.

[[hooks.commentAddedHook]]hooks.commentAddedHook::
+
Optional filename for the comment added hook, if not specified then
`comment-added` will be used.

[[hooks.changeMergedHook]]hooks.changeMergedHook::
+
Optional filename for the change merged hook, if not specified then
`change-merged` will be used.

[[hooks.mergeFailedHook]]hooks.mergeFailedHook::
+
Optional filename for the merge failed hook, if not specified then
`merge-failed` will be used.

[[hooks.changeAbandonedHook]]hooks.changeAbandonedHook::
+
Optional filename for the change abandoned hook, if not specified then
`change-abandoned` will be used.

[[hooks.changeRestoredHook]]hooks.changeRestoredHook::
+
Optional filename for the change restored hook, if not specified then
`change-restored` will be used.

[[hooks.refUpdatedHook]]hooks.refUpdatedHook::
+
Optional filename for the ref updated hook, if not specified then
`ref-updated` will be used.

[[hooks.reviewerAddedHook]]hooks.reviewerAddedHook::
+
Optional filename for the reviewer added hook, if not specified then
`reviewer-added` will be used.

[[hooks.topicChangedHook]]hooks.topicChangedHook::
+
Optional filename for the topic changed hook, if not specified then
`topic-changed` will be used.

[[hooks.claSignedHook]]hooks.claSignedHook::
+
Optional filename for the CLA signed hook, if not specified then
`cla-signed` will be used.

[[hooks.refUpdateHook]]hooks.refUpdateHook::
+
Optional filename for the ref update hook, if not specified then
`ref-update` will be used.

[[hooks.syncHookTimeout]]hooks.syncHookTimeout::
+
Optional timeout value in seconds for synchronous hooks, if not specified
then 30 seconds will be used.

[[http]]
=== Section http

[[http.proxy]]http.proxy::
+
URL of the proxy server when making outgoing HTTP
connections for OpenID login transactions.  Syntax
should be `http://`'hostname'`:`'port'.

[[http.proxyUsername]]http.proxyUsername::
+
Optional username to authenticate to the HTTP proxy with.
This property is honored only if the username does not
appear in the http.proxy property above.

[[http.proxyPassword]]http.proxyPassword::
+
Optional password to authenticate to the HTTP proxy with.
This property is honored only if the password does not
appear in the http.proxy property above.


[[httpd]]
=== Section httpd

The httpd section configures the embedded servlet container.

[[httpd.listenUrl]]httpd.listenUrl::
+
Specifies the URLs the internal HTTP daemon should listen for
connections on.  The special hostname '*' may be used to listen
on all local addresses.  A context path may optionally be included,
placing Gerrit Code Review's web address within a subdirectory of
the server.
+
Multiple protocol schemes are supported:
+
* `http://`'hostname'`:`'port'
+
Plain-text HTTP protocol.  If port is not supplied, defaults to 80,
the standard HTTP port.
+
* `https://`'hostname'`:`'port'
+
SSL encrypted HTTP protocol.  If port is not supplied, defaults to
443, the standard HTTPS port.
+
Externally facing production sites are encouraged to use a reverse
proxy configuration and `proxy-https://` (below), rather than using
the embedded servlet container to implement the SSL processing.
The proxy server with SSL support is probably easier to configure,
provides more configuration options to control cipher usage, and
is likely using natively compiled encryption algorithms, resulting
in higher throughput.
+
* `proxy-http://`'hostname'`:`'port'
+
Plain-text HTTP relayed from a reverse proxy.  If port is not
supplied, defaults to 8080.
+
Like http, but additional header parsing features are
enabled to honor X-Forwarded-For, X-Forwarded-Host and
X-Forwarded-Server.  These headers are typically set by Apache's
link:http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#x-headers[mod_proxy].
+
* `proxy-https://`'hostname'`:`'port'
+
Plain text HTTP relayed from a reverse proxy that has already
handled the SSL encryption/decryption.  If port is not supplied,
defaults to 8080.
+
Behaves exactly like proxy-http, but also sets the scheme to assume
'https://' is the proper URL back to the server.

+
If multiple values are supplied, the daemon will listen on all
of them.
+
By default, http://*:8080.

[[httpd.reuseAddress]]httpd.reuseAddress::
+
If true, permits the daemon to bind to the port even if the port
is already in use.  If false, the daemon ensures the port is not
in use before starting.  Busy sites may need to set this to true
to permit fast restarts.
+
By default, true.

[[httpd.requestHeaderSize]]httpd.requestHeaderSize::
+
Size, in bytes, of the buffer used to parse the HTTP headers of an
incoming HTTP request.  The entire request headers, including any
cookies sent by the browser, must fit within this buffer, otherwise
the server aborts with the response '413 Request Entity Too Large'.
+
One buffer of this size is allocated per active connection.
Allocating a buffer that is too large wastes memory that cannot be
reclaimed, allocating a buffer that is too small may cause unexpected
errors caused by very long Referer URLs or large cookie values.
+
By default, 16384 (16 K), which is sufficient for most OpenID and
other web-based single-sign-on integrations.

[[httpd.sslCrl]]httpd.sslCrl::
+
Path of the certificate revocation list file in PEM format. This
crl file is optional, and available for CLIENT_SSL_CERT_LDAP
authentication.
+
To create and view a crl using openssl:
+
----
openssl ca -gencrl -out crl.pem
openssl crl -in crl.pem -text
----
+
If not absolute, the path is resolved relative to `$site_path`.
+
By default, `$site_path/etc/crl.pem`.

[[httpd.sslKeyStore]]httpd.sslKeyStore::
+
Path of the Java keystore containing the server's SSL certificate
and private key.  This keystore is required for `https://` in URL.
+
To create a self-signed certificate for simple internal usage:
+
----
keytool -keystore keystore -alias jetty -genkey -keyalg RSA
chmod 600 keystore
----
+
If not absolute, the path is resolved relative to `$site_path`.
+
By default, `$site_path/etc/keystore`.

[[httpd.sslKeyPassword]]httpd.sslKeyPassword::
+
Password used to decrypt the private portion of the sslKeyStore.
Java keystores require a password, even if the administrator
doesn't want to enable one.
+
If set to the empty string the embedded server will prompt for the
password during startup.
+
By default, `gerrit`.

[[httpd.requestLog]]httpd.requestLog::
+
Enable (or disable) the `'$site_path'/logs/httpd_log` request log.
If enabled, an NCSA combined log format request log file is written
out by the internal HTTP daemon.
+
`log4j.appender` with the name `httpd_log` can be configured to overwrite
programmatic configuration.
+
By default, true if httpd.listenUrl uses http:// or https://,
and false if httpd.listenUrl uses proxy-http:// or proxy-https://.

[[httpd.acceptorThreads]]httpd.acceptorThreads::
+
Number of worker threads dedicated to accepting new incoming TCP
connections and allocating them connection-specific resources.
+
By default, 2, which should be suitable for most high-traffic sites.

[[httpd.minThreads]]httpd.minThreads::
+
Minimum number of spare threads to keep in the worker thread pool.
This number must be at least 1 larger than httpd.acceptorThreads
multiplied by the number of httpd.listenUrls configured.
+
By default, 5, suitable for most lower-volume traffic sites.

[[httpd.maxThreads]]httpd.maxThreads::
+
Maximum number of threads to permit in the worker thread pool.
+
By default 25, suitable for most lower-volume traffic sites.

[[httpd.maxQueued]]httpd.maxQueued::
+
Maximum number of client connections which can enter the worker
thread pool waiting for a worker thread to become available.
0 disables the queue and permits infinite number of connections.
+
By default 50.

[[httpd.maxWait]]httpd.maxWait::
+
Maximum amount of time a client will wait for an available
thread to handle a project clone, fetch or push request over the
smart HTTP transport.
+
Values should use common unit suffixes to express their setting:
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days
* w, week, weeks (`1 week` is treated as `7 days`)
* mon, month, months (`1 month` is treated as `30 days`)
* y, year, years (`1 year` is treated as `365 days`)

+
If a unit suffix is not specified, `minutes` is assumed.  If 0
is supplied, the maximum age is infinite and connections will not
abort until the client disconnects.
+
By default, 5 minutes.

[[httpd.filterClass]]httpd.filterClass::
+
Class that implements the javax.servlet.Filter interface
for filtering any HTTP related traffic going through the Gerrit
HTTP protocol.
Class is loaded and configured in the Gerrit Jetty container
and run in front of all Gerrit URL handlers, allowing the filter
to inspect, modify, allow or reject each request.
It needs to be provided as JAR library
under $GERRIT_SITE/lib as it is resolved using the default Gerrit class
loader and cannot be dynamically loaded by a plugin.
+
Failing to load the Filter class would result in a Gerrit start-up
failure, as this class is supposed to provide mandatory filtering
in front of Gerrit HTTP protocol.
+
Typical usage is in conjunction with the `auth.type=HTTP` as replacement
of an Apache HTTP proxy layer as security enforcement on top of Gerrit
by returning a trusted username as HTTP Header.
+
Example of using a security library secure.jar under $GERRIT_SITE/lib
that provides a org.anyorg.MySecureFilter Servlet Filter that enforces
a trusted username in the `TRUSTED_USER` HTTP Header:

----
[auth]
	type = HTTP
	httpHeader = TRUSTED_USER

[http]
	filterClass = org.anyorg.MySecureFilter
----

[[httpd.robotsFile]]httpd.robotsFile::
+
Location of an external robots.txt file to be used instead of the one
bundled with the .war of the application.
+
If not absolute, the path is resolved relative to `$site_path`.
+
If the file doesn't exist or can't be read the default robots.txt file
bundled with the .war will be used instead.

[[index]]
=== Section index

The index section configures the secondary index.

[[index.type]]index.type::
+
Type of secondary indexing employed by Gerrit.  The supported
values are:
+
* `LUCENE`
+
A link:http://lucene.apache.org/[Lucene] index is used.
+
* `SOLR`
+
A link:https://cwiki.apache.org/confluence/display/solr/SolrCloud[
SolrCloud] index is used.

+
By default, `LUCENE`.
+
After changing the secondary index type, the index must be rebuilt
using the link:pgm-reindex.html[reindex program] before restarting the
Gerrit server.

Open and closed changes are indexed in separate indexes named
'changes_open' and 'changes_closed' respectively.

[[index.url]]index.url::
+
Only used when the type is `SOLR`.
+
URL of the index server.

[[index.name.ramBufferSize]]index.name.ramBufferSize::
+
Only used when the type is `LUCENE`.
+
Determines the amount of RAM that may be used for buffering added documents
and deletions before they are flushed to the index.  See the
link:http://lucene.apache.org/core/4_6_0/core/org/apache/lucene/index/LiveIndexWriterConfig.html#setRAMBufferSizeMB(double)[
Lucene documentation] for further details.
+
Defaults to 16M.

[[index.name.maxBufferedDocs]]index.name.maxBufferedDocs::
+
Only used when the type is `LUCENE`.
+
Determines the minimal number of documents required before the buffered
in-memory documents are flushed to the index. Large values generally
give faster indexing.  See the
link:http://lucene.apache.org/core/4_6_0/core/org/apache/lucene/index/LiveIndexWriterConfig.html#setMaxBufferedDocs(int)[
Lucene documentation] for further details.
+
Defaults to -1, meaning no maximum is set and the writer will flush
according to RAM usage.

[[index.name.commitWithin]]index.name.commitWithin::
+
Only used when the type is `LUCENE`.
+
Determines the period at which changes are automatically committed to
stable store on disk. This is a costly operation and may block
additional index writes, so lower with caution.
+
If zero or negative, changes are committed after every write. This is
very costly but may be useful if offline reindexing is infeasible, or
for development servers.
+
Defaults to 300000 ms (5 minutes).

Sample index configuration:
----
[index]
  type = LUCENE

[index "changes_open"]
  ramBufferSize = 60 m
  maxBufferedDocs = 3000

[index "changes_closed"]
  ramBufferSize = 20 m
  maxBufferedDocs = 500
----

[[ldap]]
=== Section ldap

LDAP integration is only enabled if `auth.type` is set to
`HTTP_LDAP`, `LDAP` or `CLIENT_SSL_CERT_LDAP`.  See above for a
detailed description of the `auth.type` settings and their
implications.

An example LDAP configuration follows, and then discussion of
the parameters introduced here.  Suitable defaults for most
parameters are automatically guessed based on the type of server
detected during startup.  The guessed defaults support both
link:http://www.ietf.org/rfc/rfc2307.txt[RFC 2307] and Active
Directory.

----
[ldap]
  server = ldap://ldap.example.com

  accountBase = ou=people,dc=example,dc=com
  accountPattern = (&(objectClass=person)(uid=${username}))
  accountFullName = displayName
  accountEmailAddress = mail

  groupBase = ou=groups,dc=example,dc=com
  groupMemberPattern = (&(objectClass=group)(member=${dn}))
----

[[ldap.server]]ldap.server::
+
URL of the organization's LDAP server to query for user information
and group membership from.  Must be of the form `ldap://host` or
`ldaps://host` to bind with either a plaintext or SSL connection.
+
If `auth.type` is `LDAP` this setting should use `ldaps://` to
ensure the end user's plaintext password is transmitted only over
an encrypted connection.

[[ldap.sslVerify]]ldap.sslVerify::
+
If false and ldap.server is an `ldaps://` style URL, Gerrit
will not verify the server certificate when it connects to
perform a query.
+
By default, true, requiring the certificate to be verified.

[[ldap.username]]ldap.username::
+
_(Optional)_ Username to bind to the LDAP server with.  If not set,
an anonymous connection to the LDAP server is attempted.

[[ldap.password]]ldap.password::
+
_(Optional)_ Password for the user identified by `ldap.username`.
If not set, an anonymous (or passwordless) connection to the LDAP
server is attempted.

[[ldap.referral]]ldap.referral::
+
_(Optional)_ How an LDAP referral should be handled if it is
encountered during directory traversal.  Set to `follow` to
automatically follow any referrals, or `ignore` to ignore the
referrals.
+
By default, `ignore`.

[[ldap.readTimeout]]ldap.readTimeout::
+
_(Optional)_ The read timeout for an LDAP operation. The value is
in the usual time-unit format like "1 s", "100 ms", etc...
A timeout can be used to avoid blocking all of the SSH command start
threads in case the LDAP server becomes slow.
+
By default there is no timeout and Gerrit will wait for the LDAP
server to respond until the TCP connection times out.

[[ldap.accountBase]]ldap.accountBase::
+
Root of the tree containing all user accounts.  This is typically
of the form `ou=people,dc=example,dc=com`.

[[ldap.accountScope]]ldap.accountScope::
+
Scope of the search performed for accounts.  Must be one of:
+
* `one`: Search only one level below accountBase, but not recursive
* `sub` or `subtree`: Search recursively below accountBase
* `base` or `object`: Search exactly accountBase; probably not desired

+
Default is `subtree` as many directories have several levels.

[[ldap.accountPattern]]ldap.accountPattern::
+
Query pattern to use when searching for a user account.  This may be
any valid LDAP query expression, including the standard `(&...)` and
`(|...)` operators.  If `auth.type` is `HTTP_LDAP` then the variable
`${username}` is replaced with a parameter set to the username
that was supplied by the HTTP server.  If `auth.type` is `LDAP` then
the variable `${username}` is replaced by the string entered by
the end user.
+
This pattern is used to search the objects contained directly under
the `ldap.accountBase` tree.  A typical setting for this parameter
is `(uid=${username})` or `(cn=${username})`, but the proper
setting depends on the LDAP schema used by the directory server.
+
Default is `(uid=${username})` for RFC 2307 servers,
and `(&(objectClass=user)(sAMAccountName=${username}))`
for Active Directory.

[[ldap.accountFullName]]ldap.accountFullName::
+
_(Optional)_ Name of an attribute on the user account object which
contains the initial value for the user's full name field in Gerrit.
Typically this is the `displayName` property in LDAP, but could
also be `legalName` or `cn`.
+
Attribute values may be concatenated with literal strings.  For
example to join given name and surname together, use the pattern
`${givenName} ${SN}`.
+
If set, users will be unable to modify their full name field, as
Gerrit will populate it only from the LDAP data.
+
Default is `displayName` for RFC 2307 servers,
and `${givenName} ${sn}` for Active Directory.

[[ldap.accountEmailAddress]]ldap.accountEmailAddress::
+
_(Optional)_ Name of an attribute on the user account object which
contains the user's Internet email address, as defined by this
LDAP server.
+
Attribute values may be concatenated with literal strings,
for example to set the email address to the lowercase form
of sAMAccountName followed by a constant domain name, use
`${sAMAccountName.toLowerCase}@example.com`.
+
If set, the preferred email address will be prefilled from LDAP,
but users may still be able to register additional email addresses,
and select a different preferred email address.
+
Default is `mail`.

[[ldap.accountSshUserName]]ldap.accountSshUserName::
+
_(Optional)_ Name of an attribute on the user account object which
contains the initial value for the user's SSH username field in
Gerrit.  Typically this is the `uid` property in LDAP, but could
also be `cn`.  Administrators should prefer to match the attribute
corresponding to the user's workstation username, as this is what
SSH clients will default to.
+
Attribute values may also be forced to lowercase, or to uppercase in
an expression.  For example, `${sAMAccountName.toLowerCase}` will
force the value of sAMAccountName, if defined, to be all lowercase.
The suffix `.toUpperCase` can be used for the other direction.
The suffix `.localPart` can be used to split attribute values of
the form 'user@example.com' and return only the left hand side, for
example `${userPrincipalName.localPart}` would provide only 'user'.
+
If set, users will be unable to modify their SSH username field, as
Gerrit will populate it only from the LDAP data.
+
Default is `uid` for RFC 2307 servers,
and `${sAMAccountName.toLowerCase}` for Active Directory.

[[ldap.accountMemberField]]ldap.accountMemberField::
+
_(Optional)_ Name of an attribute on the user account object which
contains the groups the user is part of. Typically used for Active
Directory servers.
+
Default is unset for RFC 2307 servers (disabled)
and `memberOf` for Active Directory.

[[ldap.groupBase]]ldap.groupBase::
+
Root of the tree containing all group objects.  This is typically
of the form `ou=groups,dc=example,dc=com`.

[[ldap.groupScope]]ldap.groupScope::
+
Scope of the search performed for group objects.  Must be one of:
+
* `one`: Search only one level below groupBase, but not recursive
* `sub` or `subtree`: Search recursively below groupBase
* `base` or `object`: Search exactly groupBase; probably not desired

+
Default is `subtree` as many directories have several levels.

[[ldap.groupPattern]]ldap.groupPattern::
+
Query pattern used when searching for an LDAP group to connect
to a Gerrit group.  This may be any valid LDAP query expression,
including the standard `(&...)` and `(|...)` operators.  The variable
`${groupname}` is replaced with the search term supplied by the
group owner.
+
Default is `(cn=${groupname})` for RFC 2307,
and `(&(objectClass=group)(cn=${groupname}))` for Active Directory.

[[ldap.groupMemberPattern]]ldap.groupMemberPattern::
+
Query pattern to use when searching for the groups that a user
account is currently a member of.  This may be any valid LDAP query
expression, including the standard `(&...)` and `(|...)` operators.
+
If `auth.type` is `HTTP_LDAP` then the variable `${username}` is
replaced with a parameter set to the username that was supplied
by the HTTP server.  Other variables appearing in the pattern,
such as `${fooBarAttribute}`, are replaced with the value of the
corresponding attribute (in this case, `fooBarAttribute`) as read
from the user's account object matched under `ldap.accountBase`.
Attributes such as `${dn}` or `${uidNumber}` may be useful.
+
Default is `(|(memberUid=${username})(gidNumber=${gidNumber}))` for
RFC 2307, and unset (disabled) for Active Directory.

[[ldap.groupName]]ldap.groupName::
+
_(Optional)_ Name of the attribute on the group object which contains
the value to use as the group name in Gerrit.
+
Typically the attribute name is `cn` for RFC 2307 and Active Directory
servers.  For other servers the attribute name may differ, for example
`apple-group-realname` on Apple MacOS X Server.
+
It is also possible to specify a literal string containing a pattern of
attribute values.  For example to create a Gerrit group name consisting of
LDAP group name and group ID, use the pattern `${cn} (${gidNumber})`.
+
Default is `cn`.

[[ldap.localUsernameToLowerCase]]ldap.localUsernameToLowerCase::
+
Converts the local username, that is used to login into the Gerrit
WebUI, to lower case before doing the LDAP authentication. By setting
this parameter to true, a case insensitive login to the Gerrit WebUI
can be achieved.
+
If set, it must be ensured that the local usernames for all existing
accounts are converted to lower case, otherwise a user that has a
local username that contains upper case characters will not be able to login
anymore. The local usernames for the existing accounts can be
converted to lower case by running the server program
link:pgm-LocalUsernamesToLowerCase.html[LocalUsernamesToLowerCase].
Please be aware that the conversion of the local usernames to lower
case can't be undone. For newly created accounts the local username
will be directly stored in lower case.
+
By default, unset/false.

[[ldap.authentication]]ldap.authentication::
+
Defines how Gerrit authenticates with the server. When set to `GSSAPI`
Gerrit will use Kerberos. To use kerberos the
`java.security.auth.login.config` system property must point to a
login to a JAAS configuration file and, if Java 6 is used, the system
property `java.security.krb5.conf` must point to the appropriate
krb5.ini file with references to the KDC.

Typical jaas.conf.

----
KerberosLogin {
    com.sun.security.auth.module.Krb5LoginModule
            required
            useTicketCache=true
            doNotPrompt=true
            renewTGT=true;
};
----

See Java documentation on how to create the krb5.ini file.

Note the `renewTGT` property to make sure the TGT does not expire,
and `useTicketCache` to use the TGT supplied by the operating system. As
the whole point of using GSSAPI is to have passwordless authentication
to the LDAP service, this option does not acquire a new TGT on its own.

On Windows servers the registry key `HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters`
must have the DWORD value `allowtgtsessionkey` set to 1 and the account must not
have local administrator privileges.

[[mimetype]]
=== Section mimetype

[[mimetype.name.safe]]mimetype.<name>.safe::
+
If set to true, files with the MIME type `<name>` will be sent as
direct downloads to the user's browser, rather than being wrapped up
inside of zipped archives.  The type name may be a complete type
name, e.g. `image/gif`, a generic media type, e.g. `image/*`,
or the wildcard `*/*` to match all types.
+
By default, false for all MIME types.

Common examples:
----
[mimetype "image/*"]
  safe = true

[mimetype "application/pdf"]
  safe = true

[mimetype "application/msword"]
  safe = true

[mimetype "application/vnd.ms-excel"]
  safe = true
----


[[pack]]
=== Section pack

Global settings controlling how Gerrit Code Review creates pack
streams for Git clients running clone, fetch, or pull.  Most of these
variables are per-client request, and thus should be carefully set
given the expected concurrent request load and available CPU and
memory resources.

[[pack.deltacompression]]pack.deltacompression::
+
If true, delta compression between objects is enabled.  This may
result in a smaller overall transfer for the client, but requires
more server memory and CPU time.
+
False (off) by default, matching Gerrit Code Review 2.1.4.

[[pack.threads]]pack.threads::
+
Maximum number of threads to use for delta compression (if enabled).
This is per-client request.  If set to 0 then the number of CPUs is
auto-detected and one thread per CPU is used, per client request.
+
By default, 1.


[[plugins]]
=== Section plugins

[[plugins.checkFrequency]]plugins.checkFrequency::
+
How often plugins should be examined for new plugins to load, removed
plugins to be unloaded, or updated plugins to be reloaded.  Values can
be specified using standard time unit abbreviations ('ms', 'sec',
'min', etc.).
+
If set to 0, automatic plugin reloading is disabled.  Administrators
may force reloading with link:cmd-plugin.html[gerrit plugin reload].
+
Default is 1 minute.

[[plugins.allowRemoteAdmin]]plugins.allowRemoteAdmin::
+
Enable remote installation, enable and disable of plugins over HTTP
and SSH.  If set to true Administrators can install new plugins
remotely, or disable existing plugins.  Defaults to false.


[[receive]]
=== Section receive

This section is used to set who can execute the 'receive-pack' and
to limit the maximum Git object size that 'receive-pack' will accept.
'receive-pack' is what runs on the server during a user's push or
repo upload command. It also contains some advanced options for tuning the
behavior of Gerrit's 'receive-pack' mechanism.

----
[receive]
  allowGroup = GROUP_ALLOWED_TO_EXECUTE
  allowGroup = YET_ANOTHER_GROUP_ALLOWED_TO_EXECUTE
  maxObjectSizeLimit = 40 m
----

[[receive.checkMagicRefs]]receive.checkMagicRefs::
+
If true, Gerrit will verify the destination repository has
no references under the magic 'refs/drafts', 'refs/for', or
'refs/publish' branch namespaces. Names under these locations
confuse clients when trying to upload code reviews so Gerrit
requires them to be empty.
+
If false Gerrit skips the sanity check and assumes administrators
have ensured the repository does not contain any magic references.
Setting to false to skip the check can decrease latency during push.
+
Default is true.

[[receive.checkReferencedObjectsAreReachable]]receive.checkReferencedObjectsAreReachable::
+
If set to true, Gerrit will validate that all referenced objects that
are not included in the received pack are reachable by the user.
+
Carrying out this check on gits with many refs and commits can be a
very CPU-heavy operation. For non public Gerrit-servers this check may
be overkill.
+
Only disable this check if you trust the clients not to forge SHA1
references to access commits intended to be hidden from the user.
+
Default is true.

[[receive.allowGroup]]receive.allowGroup::
+
Name of the groups of users that are allowed to execute
'receive-pack' on the server. One or more groups can be set.
+
If no groups are added, any user will be allowed to execute
'receive-pack' on the server.

[[receive.maxObjectSizeLimit]]receive.maxObjectSizeLimit::
+
Maximum allowed Git object size that 'receive-pack' will accept.
If an object is larger than the given size the pack-parsing will abort
and the push operation will fail. If set to zero then there is no
limit.
+
Gerrit administrators can use this setting to prevent developers
from pushing objects which are too large to Gerrit.
+
This setting can also be set in the `project.config`
link:config-project-config.html[receive.maxObjectSizeLimit] in order
to further reduce the global setting. The project specific setting is
only honored when it further reduces the global limit.
+
Default is zero.
+
Common unit suffixes of 'k', 'm', or 'g' are supported.

[[receive.threadPoolSize]]receive.threadPoolSize::
+
Maximum size of the thread pool in which the change data in received packs is
processed.
+
Defaults to the number of available CPUs according to the Java runtime.

[[receive.changeUpdateThreads]]receive.changeUpdateThreads::
+
Number of threads to perform change creation or patch set updates
concurrently. Each thread uses its own database connection from
the database connection pool, and if all threads are busy then
main receive thread will also perform a change creation or patch
set update.
+
Defaults to 1, using only the main receive thread. This feature is for
databases with very high latency that can benefit from concurrent
operations when multiple changes are impacted at once.

[[receive.timeout]]receive.timeout::
+
Overall timeout on the time taken to process the change data in
received packs. Only includes the time processing Gerrit changes
and updating references, not the time to index the pack. Values can
be specified using standard time unit abbreviations ('ms', 'sec',
'min', etc.).
+
Default is 2 minutes. If no unit is specified, milliseconds
is assumed.


[[repository]]
=== Section repository

Repositories in this sense are the same as projects.

In the following example configuration `Registered Users` is set
to be the default owner of new projects.

----
[repository "*"]
  ownerGroup = Registered Users
----

[NOTE]
Currently only the repository name `*` is supported.
This is a wildcard designating all repositories.

[[repository.name.defaultSubmitType]]repository.<name>.defaultSubmitType::
+
The default submit type for newly created projects. Supported values
are `MERGE_IF_NECESSARY`, `FAST_FORWARD_ONLY`, `REBASE_IF_NECESSARY`,
`MERGE_ALWAYS` and `CHERRY_PICK`.
+
By default, `MERGE_IF_NECESSARY`.

[[repository.name.ownerGroup]]repository.<name>.ownerGroup::
+
A name of a group which exists in the database. Zero, one or many
groups are allowed.  Each on its own line.  Groups which don't exist
in the database are ignored.

[[rules]]
=== Section rules

[[rules.enable]]rules.enable::
+
If true, Gerrit will load and execute 'rules.pl' files in each
project's refs/meta/config branch, if present. When set to false,
only the default internal rules will be used.
+
Default is true, to execute project specific rules.

[[sendemail]]
=== Section sendemail

[[sendemail.enable]]sendemail.enable::
+
If false Gerrit will not send email messages, for any reason,
and all other properties of section sendemail are ignored.
+
By default, true, allowing notifications to be sent.

[[sendemail.from]]sendemail.from::
+
Designates what name and address Gerrit will place in the From
field of any generated email messages.  The supported values are:
+
* `USER`
+
Gerrit will set the From header to use the current user's
Full Name and Preferred Email.  This may cause messages to be
classified as spam if the user's domain has SPF or DKIM enabled
and <<sendemail.smtpServer,sendemail.smtpServer>> is not a trusted
relay for that domain.
+
* `MIXED`
+
Shorthand for `${user} (Code Review) <review@example.com>` where
`review@example.com` is the same as <<user.email,user.email>>.
See below for a description of how the replacement is handled.
+
* `SERVER`
+
Gerrit will set the From header to the same name and address
it records in any commits Gerrit creates.  This is set by
<<user.name,user.name>> and <<user.email,user.email>>, or guessed
from the local operating system.
+
* 'Code Review' `<`'review'`@`'example.com'`>`
+
If set to a name and email address in brackets, Gerrit will use
this name and email address for any messages, overriding the name
that may have been selected for commits by user.name and user.email.
Optionally, the name portion may contain the placeholder `${user}`,
which is replaced by the Full Name of the current user.

+
By default, MIXED.

[[sendemail.smtpServer]]sendemail.smtpServer::
+
Hostname (or IP address) of a SMTP server that will relay
messages generated by Gerrit to end users.
+
By default, 127.0.0.1 (aka localhost).

[[sendemail.smtpServerPort]]sendemail.smtpServerPort::
+
Port number of the SMTP server in sendemail.smtpserver.
+
By default, 25, or 465 if smtpEncryption is 'ssl'.

[[sendemail.smtpEncryption]]sendemail.smtpEncryption::
+
Specify the encryption to use, either 'ssl' or 'tls'.
+
By default, 'none', indicating no encryption is used.

[[sendemail.sslVerify]]sendemail.sslVerify::
+
If false and sendemail.smtpEncryption is 'ssl' or 'tls', Gerrit
will not verify the server certificate when it connects to send
an email message.
+
By default, true, requiring the certificate to be verified.

[[sendemail.smtpUser]]sendemail.smtpUser::
+
User name to authenticate with, if required for relay.

[[sendemail.smtpPass]]sendemail.smtpPass::
+
Password for the account named by sendemail.smtpUser.

[[sendemail.allowrcpt]]sendemail.allowrcpt::
+
If present, each value adds one entry to the whitelist of email
addresses that Gerrit can send email to.  If set to a complete
email address, that one address is added to the white list.
If set to a domain name, any address at that domain can receive
email from Gerrit.
+
By default, unset, permitting delivery to any email address.

[[sendemail.includeDiff]]sendemail.includeDiff::
+
If true, new change emails and merged change emails from Gerrit
will include the complete unified diff of the change.
Variable maxmimumDiffSize places an upper limit on how large the
email can get when this option is enabled.
+
By default, false.

[[sendemail.maximumDiffSize]]sendemail.maximumDiffSize::
+
Largest size of unified diff output to include in an email. When
the diff exceeds this size the file paths will be listed instead.
Standard byte unit suffixes are supported.
+
By default, 256 KiB.

[[sendemail.importance]]sendemail.importance::
+
If present, emails sent from Gerrit will have the given level
of importance. Valid values include 'high' and 'low', which
email clients will render in different ways.
+
By default, unset, so no Importance header is generated.

[[sendemail.expiryDays]]sendemail.expiryDays::
+
If present, emails sent from Gerrit will expire after the given
number of days. This will add the Expiry-Date header and
email clients may expire or expunge mails whose Expiry-Date
header is in the past. This should be a positive non-zero
number indicating how many days in the future the mails
should expire.
+
By default, unset, so no Expiry-Date header is generated.


[[site]]
=== Section site

[[site.refreshHeaderFooter]]site.refreshHeaderFooter::
+
If true the server checks the site header, footer and CSS files for
updated versions. If false, a server restart is required to change
any of these resources. Default is true, allowing automatic reloads.

[[site.enableDeprecatedQuery]]site.enableDeprecatedQuery::
+
If true the deprecated `/query` URL is available to return JSON
and text results for changes. If false, the URL is disabled and
returns 404 to clients. Default is true, enabling `/query`.

[[ssh-alias]]
=== Section ssh-alias

Variables in section ssh-alias permit the site administrator to alias
another command from Gerrit or a plugin into the `gerrit` command
namespace. To alias `replication start` to `gerrit replicate`:

----
[ssh-alias]
  replicate = replication start
----

[[sshd]]
=== Section sshd

[[sshd.listenAddress]]sshd.listenAddress::
+
Specifies the local addresses the internal SSHD should listen
for connections on.  The following forms may be used to specify
an address.  In any form, `:'port'` may be omitted to use the
default of 29418.
+
* 'hostname':'port' (for example `review.example.com:29418`)
* 'IPv4':'port' (for example `10.0.0.1:29418`)
* ['IPv6']:'port' (for example `[ff02::1]:29418`)
* *:'port' (for example `*:29418`)

+
If multiple values are supplied, the daemon will listen on all
of them.
+
To disable the internal SSHD, set listenAddress to `off`.
+
By default, *:29418.

[[sshd.advertisedAddress]]sshd.advertisedAddress::
+
Specifies the addresses clients should be told to connect to.
This may differ from sshd.listenAddress if a firewall based port
redirector is being used, making Gerrit appear to answer on port
22. The following forms may be used to specify an address.  In any
form, `:'port'` may be omitted to use the default SSH port of 22.
+
* 'hostname':'port' (for example `review.example.com:22`)
* 'IPv4':'port' (for example `10.0.0.1:29418`)
* ['IPv6']:'port' (for example `[ff02::1]:29418`)

+
If multiple values are supplied, the daemon will advertise all
of them.
+
By default, sshd.listenAddress.

[[sshd.tcpKeepAlive]]sshd.tcpKeepAlive::
+
If true, enables TCP keepalive messages to the other side, so
the daemon can terminate connections if the peer disappears.
+
Only effective when `sshd.backend` is set to `MINA`.
+
By default, true.

[[sshd.threads]]sshd.threads::
+
Number of threads to use when executing SSH command requests.
If additional requests are received while all threads are busy they
are queued and serviced in a first-come-first-served order.
+
By default, 1.5x the number of CPUs available to the JVM.

[[sshd.batchThreads]]sshd.batchThreads::
+
Number of threads to allocate for SSH command requests from
link:access-control.html#non-interactive_users[non-interactive users].
If equals to 0, then all non-interactive requests are executed in the same
queue as interactive requests.
+
Any other value will remove the number of threads from the queue
allocated to interactive users, and create a separate thread pool
of the requested size, which will be used to run commands from
non-interactive users.
+
If the number of threads requested for non-interactive users is larger
than the total number of threads allocated in sshd.threads, then the
value of sshd.threads is increased to accommodate the requested value.
+
By default, 0.

[[sshd.streamThreads]]sshd.streamThreads::
+
Number of threads to use when formatting events to asynchronous
streaming clients.  Event formatting is multiplexed onto this thread
pool by a simple FIFO scheduling system.
+
By default, 1 plus the number of CPUs available to the JVM.

[[sshd.commandStartThreads]]sshd.commandStartThreads::
+
Number of threads used to parse a command line submitted by a client
over SSH for execution, create the internal data structures used by
that command, and schedule it for execution on another thread.
+
By default, 2.

[[sshd.maxAuthTries]]sshd.maxAuthTries::
+
Maximum number of authentication attempts before the server
disconnects the client.  Each public key that a client has loaded
into its local agent counts as one auth request.  Users can work
around the server's limit by loading less keys into their agent,
or selecting a specific key in their `~/.ssh/config` file with
the `IdentityFile` option.
+
By default, 6.

[[sshd.loginGraceTime]]sshd.loginGraceTime::
+
Time in seconds that a client has to authenticate before the server
automatically terminates their connection.  Values should use common
unit suffixes to express their setting:
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days

+
By default, 2 minutes.

[[sshd.idleTimeout]]sshd.idleTimeout::
+
Time in seconds after which the server automatically terminates idle
connections (or 0 to disable closing of idle connections).  Values
should use common unit suffixes to express their setting:
+
* s, sec, second, seconds
* m, min, minute, minutes
* h, hr, hour, hours
* d, day, days

+
By default, 0.

[[sshd.maxConnectionsPerUser]]sshd.maxConnectionsPerUser::
+
Maximum number of concurrent SSH sessions that a user account
may open at one time.  This is the number of distinct SSH logins
that each user may have active at one time, and is not related to
the number of commands a user may issue over a single connection.
If set to 0, there is no limit.
+
By default, 64.

[[sshd.cipher]]sshd.cipher::
+
Available ciphers.  To permit multiple ciphers, specify multiple
`sshd.cipher` keys in the configuration file, one cipher name
per key.  Cipher names starting with `+` are enabled in addition
to the default ciphers, cipher names starting with `-` are removed
from the default cipher set.
+
Supported ciphers: aes128-cbc, aes128-cbc, aes256-cbc, blowfish-cbc,
3des-cbc, none.
+
By default, all supported ciphers except `none` are available.

[[sshd.mac]]sshd.mac::
+
Available MAC (message authentication code) algorithms.  To permit
multiple algorithms, specify multiple `sshd.mac` keys in the
configuration file, one MAC per key.  MAC names starting with `+`
are enabled in addition to the default MACs, MAC names starting with
`-` are removed from the default MACs.
+
Supported MACs: hmac-md5, hmac-md5-96, hmac-sha1, hmac-sha1-96.
+
By default, all supported MACs are available.

[[sshd.kerberosKeytab]]sshd.kerberosKeytab::
+
Enable kerberos authentication for SSH connections.  To permit
kerberos authentication, the server must have a host principal
(see `sshd.kerberosPrincipal`) which is acquired from a keytab.
This must be provisioned by the kerberos administrators, and is
typically installed into `/etc/krb5.keytab` on host machines.
+
The keytab must contain at least one `host/` principal, typically
using the host's canonical name. If it does not use the
canonical name, the `sshd.kerberosPrincipal` should be configured
with the correct name.
+
By default, not set and so kerberos authentication is not enabled.

[[sshd.kerberosPrincipal]]sshd.kerberosPrincipal::
+
If kerberos authentication is enabled with `sshd.kerberosKeytab`,
instead use the given principal name instead of the default.
If the principal does not begin with `host/` a warning message is
printed and may prevent successful authentication.
+
This may be useful if the host is behind an IP load balancer or
other SSH forwarding systems, since the principal name is constructed
by the client and must match for kerberos authentication to work.
+
By default, `host/canonical.host.name`

[[sshd.requestLog]]sshd.requestLog::
+
Enable (or disable) the `'$site_path'/logs/sshd_log` request log.
If enabled, a request log file is written out by the SSH daemon.
+
`log4j.appender` with the name `sshd_log` can be configured to overwrite
programmatic configuration.
+
By default, true.

[[suggest]]
=== Section suggest

[[suggest.accounts]]suggest.accounts::
+
If `true`, visible user accounts (according to the value of
`accounts.visibility`) will be offered as completion suggestions
when adding a reviewer to a change, or a user to a group.
+
If `false`, account suggestion is disabled.
+
Older configurations may also have one of the `accounts.visibility`
values for this field, including `OFF` as a synonym for `NONE`. If
`accounts.visibility` is also set, that value overrides this one;
otherwise, this value applies to both `suggest.accounts` and
`accounts.visibility`.
+
New configurations should prefer the boolean value for this field
and an enum value for `accounts.visibility`.

[[suggest.from]]suggest.from::
+
The number of characters that a user must have typed before suggestions
are provided. If set to 0, suggestions are always provided.
+
By default 0.

[[theme]]
=== Section theme

[[theme.backgroundColor]]theme.backgroundColor::
+
Background color for the page, and major data tables like the all
open changes table or the account dashboard. The value must be a
valid HTML hex color code, or standard color name.
+
By default white, `FFFFFF`.

[[theme.topMenuColor]]theme.topMenuColor::
+
This is the color of the main menu bar at the top of the page.
The value must be a valid HTML hex color code, or standard color
name.
+
By default white, `FFFFFF`.

[[theme.textColor]]theme.textColor::
+
Text color for the page, and major data tables like the all
open changes table or the account dashboard. The value must be a
valid HTML hex color code, or standard color name.
+
By default dark grey, `353535`.

[[theme.trimColor]]theme.trimColor::
+
Primary color used as a background color behind text.  This is
the color of the main menu bar at the top, of table headers,
and of major UI areas that we want to offset from other portions
of the page.  The value must be a valid HTML hex color code, or
standard color name.
+
By default a light grey, `EEEEEE`.

[[theme.selectionColor]]theme.selectionColor::
+
Background color used within a trimColor area to denote the currently
selected tab, or the background color used in a table to denote the
currently selected row.  The value must be a valid HTML hex color
code, or standard color name.
+
By default a pale blue, `D8EDF9`.

[[theme.changeTableOutdatedColor]]theme.changeTableOutdatedColor::
+
Background color used for patch outdated messages.  The value must be
a valid HTML hex color code, or standard color name.
+
By default a shade of red, `F08080`.

[[theme.tableOddRowColor]]theme.tableOddRowColor::
+
Background color for tables such as lists of open reviews for odd
rows.  This is so you can have a different color for odd and even
rows of the table.  The value must be a valid HTML hex color code,
or standard color name.
+
By default transparent.

[[theme.tableEvenRowColor]]theme.tableEvenRowColor::
+
Background color for tables such as lists of open reviews for even
rows.  This is so you can have a different color for odd and even
rows of the table.  The value must be a valid HTML hex color code,
or standard color name.
+
By default transparent.

A different theme may be used for signed-in vs. signed-out user status
by using the "signed-in" and "signed-out" theme sections. Variables
not specified in a section are inherited from the default theme.

----
[theme]
  backgroundColor = FFFFFF
[theme "signed-in"]
  backgroundColor = C0C0C0
[theme "signed-out"]
  backgroundColor = 00FFFF
----

As example, here is the theme configuration to have the old green look:

----
[theme]
  backgroundColor = FCFEEF
  textColor = 000000
  trimColor = D4E9A9
  selectionColor = FFFFCC
  topMenuColor = D4E9A9
  changeTableOutdatedColor = F08080
[theme "signed-in"]
  backgroundColor = FFFFFF
----

[[trackingid]]
=== Section trackingid

Tagged footer lines containing references to external
tracking systems, parsed out of the commit message and
saved in Gerrit's database.

After making changes to this section, existing changes
must be reindexed with link:pgm-reindex.html[reindex].

The tracking ids are searchable using tr:<tracking id> or
bug:<tracking id>.

----
[trackingid "jira-bug"]
  footer = Bugfix:
  match = JRA\\d{2,8}
  system = JIRA

[trackingid "jira-feature"]
  footer = Feature
  match = JRA(\\d{2,8})
  system = JIRA
----

[[trackingid.name.footer]]trackingid.<name>.footer::
+
A prefix tag that identify the footer line to parse for tracking ids.
Several trackingid entries can have the same footer tag. A single
trackingid entry can have multiple footer tags. If multiple footer
tags are specified, each tag will be parsed separately.
(the trailing ":" is optional)

[[trackingid.name.match]]trackingid.<name>.match::
+
A link:http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html[standard
Java regular expression (java.util.regex)] used to match the
external tracking id part of the footer line. The match can
result in several entries in the DB.  If grouping is used in the
regex the first group will be interpreted as the tracking id.
Tracking ids longer than 32 characters will be ignored.
+
The configuration file parser eats one level of backslashes, so the
character class `\s` requires `\\s` in the configuration file.  The
parser also terminates the line at the first `#`, so a match
expression containing # must be wrapped in double quotes.

[[trackingid.name.system]]trackingid.<name>.system::
+
The name of the external tracking system (maximum 10 characters).
It is possible to have several trackingid entries for the same
tracking system.

[[transfer]]
=== Section transfer

[[transfer.timeout]]transfer.timeout::
+
Number of seconds to wait for a single network read or write
to complete before giving up and declaring the remote side is
not responding.  If 0, there is no timeout, and this server will
wait indefinitely for a transfer to finish.
+
A timeout should be large enough to mostly transfer the objects to
the other side.  1 second may be too small for larger projects,
especially over a WAN link, while 10-30 seconds is a much more
reasonable timeout value.
+
Defaults to 0 seconds, wait indefinitely.


[[upload]]
=== Section upload

Sets the group of users allowed to execute 'upload-pack' on the
server, 'upload-pack' is what runs on the server during a user's
fetch, clone or repo sync command.

----
[upload]
  allowGroup = GROUP_ALLOWED_TO_EXECUTE
  allowGroup = YET_ANOTHER_GROUP_ALLOWED_TO_EXECUTE
----

[[upload.allowGroup]]upload.allowGroup::
+
Name of the groups of users that are allowed to execute 'upload-pack'
on the server. One or more groups can be set.
+
If no groups are added, any user will be allowed to execute
'upload-pack' on the server.


[[user]]
=== Section user

[[user.name]]user.name::
+
Name that Gerrit calls itself in Git when it creates a new Git
commit, such as a merge during change submission.
+
By default this is "Gerrit Code Review".

[[user.email]]user.email::
+
Email address that Gerrit refers to itself as when it creates a
new Git commit, such as a merge commit during change submission.
+
If not set, Gerrit generates this as "gerrit@`hostname`", where
`hostname` is the hostname of the system Gerrit is running on.
+
By default, not set, generating the value at startup.

[[user.anonymousCoward]]user.anonymousCoward::
+
Username that is displayed in the Gerrit WebUI and in e-mail
notifications if the full name of the user is not set.
+
By default "Anonymous Coward" is used.


== File `etc/secure.config`
The optional file `'$site_path'/etc/secure.config` overrides (or
supplements) the settings supplied by `'$site_path'/etc/gerrit.config`.
The file should be readable only by the daemon process and can be
used to contain private configuration entries that wouldn't normally
be exposed to everyone.

Sample `etc/secure.config`:
----
[auth]
  registerEmailPrivateKey = 2zHNrXE2bsoylzUqDxZp0H1cqUmjgWb6
  restTokenPrivateKey = 7e40PzCjlUKOnXATvcBNXH6oyiu+r0dFk2c=

[database]
  username = webuser
  password = s3kr3t

[ldap]
  password = l3tm3srch

[httpd]
  sslKeyPassword = g3rr1t

[sendemail]
  smtpPass = sp@m

[remote "bar"]
  password = s3kr3t
----

== File `etc/peer_keys`

The optional file `'$site_path'/etc/peer_keys` controls who can
login as the 'Gerrit Code Review' user, required for the link:cmd-suexec.html[suexec]
command.

The format is one Base-64 encoded public key per line.


== Database system_config

Several columns in the `system_config` table within the metadata
database may be set to control how Gerrit behaves.

[NOTE]
The contents of the `system_config` table are cached at startup
by Gerrit.  If you modify any columns in this table, Gerrit needs
to be restarted before it will use the new values.

=== Configurable Parameters

site_path::
+
Local filesystem directory holding the site customization assets.
Placing this directory under version control and/or backup is a
good idea.
+
Files in this directory provide additional configuration.
+
Other files support site customization.
+
* link:config-themes.html[Themes]

GERRIT
------
Part of link:index.html[Gerrit Code Review]

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