tree: ce0cb3bcf7b0cdddbc3b8a4a1a62cc9bd8538444 [path history] [tgz]
  1. docs/
  2. supplements/
  3. templates/
  4. .helmignore
  5. Chart.yaml
  8. values.yaml

Gerrit on Kubernetes

Gerrit is a web-based code review tool, which acts as a Git server. This helm chart provides a Gerrit setup that can be deployed on Kubernetes. In addition, the chart provides a CronJob to perform Git garbage collection.

Gerrit versions before 3.0 are no longer supported, since the support of ReviewDB was removed.


  • Helm (>= version 3.0)

    (Check out this guide how to install and use helm.)

  • Access to a provisioner for persistent volumes with Read Write Many (RWM)- capability.

    A list of applicaple volume types can be found here. This project was developed using the NFS-server-provisioner helm chart, a NFS-provisioner deployed in the Kubernetes cluster itself. Refer to this guide of how to deploy it in context of this project.

  • A domain name that is configured to point to the IP address of the node running the Ingress controller on the kubernetes cluster (as described here).

  • (Optional: Required, if SSL is configured) A Java keystore to be used by Gerrit.

Installing the Chart

ATTENTION: The value for is required for rendering the chart's templates. The nature of the value does not allow defaults. Thus a custom values.yaml-file setting this value is required!

To install the chart with the release name gerrit, execute:

cd $(git rev-parse --show-toplevel)/helm-charts
helm install \
  gerrit \  # release name
  ./gerrit \  # path to chart
  -f <path-to-custom-values>.yaml

The command deploys the Gerrit instance on the current Kubernetes cluster. The configuration section lists the parameters that can be configured during installation.


The following sections list the configurable values in values.yaml. To configure a Gerrit setup, make a copy of the values.yaml-file and change the parameters as needed. The configuration can be applied by installing the chart as described above.

In addition, single options can be set without creating a custom values.yaml:

cd $(git rev-parse --show-toplevel)/helm-charts
helm install \
  gerrit \  # release name
  ./gerrit \  # path to chart

Container images

images.busybox.registryThe registry to pull the busybox container images
images.busybox.tagThe busybox image tag to uselatest
images.registry.nameThe image registry to pull the container images from``
images.registry.ImagePullSecret.nameName of the ImagePullSecretimage-pull-secret (if empty no image pull secret will be deployed)
images.registry.ImagePullSecret.createWhether to create an ImagePullSecretfalse
images.registry.ImagePullSecret.usernameThe image registry usernamenil
images.registry.ImagePullSecret.passwordThe image registry passwordnil
images.versionThe image version (image tag) to uselatest
images.imagePullPolicyImage pull policyAlways
images.additionalImagePullSecretsAdditional image pull policies that pods should use[]


additionalLabelsAdditional labels for resources managed by this Helm chart{}

Storage classes

For information of how a StorageClass is configured in Kubernetes, read the official Documentation.

storageClasses.default.nameThe name of the default StorageClass (RWO)default
storageClasses.default.createWhether to create the StorageClassfalse
storageClasses.default.provisionerProvisioner of the
storageClasses.default.reclaimPolicyWhether to Retain or Delete volumes, when they become unboundDelete
storageClasses.default.parametersParameters for the provisionerparameters.type: gp2, parameters.fsType: ext4
storageClasses.default.mountOptionsThe mount options of the default StorageClass[]
storageClasses.default.allowVolumeExpansionWhether to allow volume expansion.false
storageClasses.shared.nameThe name of the shared StorageClass (RWM)shared-storage
storageClasses.shared.createWhether to create the StorageClassfalse
storageClasses.shared.provisionerProvisioner of the StorageClassnfs
storageClasses.shared.reclaimPolicyWhether to Retain or Delete volumes, when they become unboundDelete
storageClasses.shared.parametersParameters for the provisionerparameters.mountOptions: vers=4.1
storageClasses.shared.mountOptionsThe mount options of the shared StorageClass[]
storageClasses.shared.allowVolumeExpansionWhether to allow volume expansion.false

Network policies

networkPolicies.enabledWhether to enable preconfigured NetworkPoliciesfalse
networkPolicies.dnsPortsList of ports used by DNS-service (e.g. KubeDNS)[53, 8053]

The NetworkPolicies provided here are quite strict and do not account for all possible scenarios. Thus, custom NetworkPolicies have to be added, e.g. for allowing Gerrit to replicate to a Gerrit replica. By default, the egress traffic of the gerrit pod is blocked, except for connections to the DNS-server. Thus, replication which requires Gerrit to perform git pushes to the replica will not work. The chart provides the possibility to define custom rules for egress- traffic of the gerrit pod under gerrit.networkPolicy.egress. Depending on the scenario, there are different ways to allow the required connections. The easiest way is to allow all egress-traffic for the gerrit pods:

    - {}

If the remote that is replicated to is running in a pod on the same cluster and the service-DNS is used as the remote's URL (e.g. http://gerrit-replica-git-backend-service:80/git/${name}.git), a podSelector (and namespaceSelector, if the pod is running in a different namespace) can be used to whitelist the traffic:

    - to:
      - podSelector:
            app: git-backend

If the remote is outside the cluster, the IP of the remote or its load balancer can also be whitelisted, e.g.:

    - to:
      - ipBlock:

The same principle also applies to other use cases, e.g. connecting to a database. For more information about the NetworkPolicy resource refer to the Kubernetes documentation.

Workaround for NFS

Kubernetes will not always be able to adapt the ownership of the files within NFS volumes. Thus, a workaround exists that will add init-containers to adapt file ownership. Note, that only the ownership of the root directory of the volume will be changed. All data contained within will be expected to already be owned by the user used by Gerrit. Also the ID-domain will be configured to ensure correct ID-mapping.

nfsWorkaround.enabledWhether the volume used is an NFS-volumefalse
nfsWorkaround.chownOnStartupWhether to chown the volume on pod startupfalse
nfsWorkaround.idDomainThe ID-domain that should be used to map user-/group-IDs for the NFS

Storage for Git repositories

gitRepositoryStorage.externalPVC.useWhether to use a PVC deployed outside the chartfalse
gitRepositoryStorage.externalPVC.nameName of the external PVCgit-repositories-pvc
gitRepositoryStorage.sizeSize of the volume storing the Git repositories5Gi

If the git repositories should be persisted even if the chart is deleted and in a way that the volume containing them can be mounted by the reinstalled chart, the PVC claiming the volume has to be created independently of the chart. To use the external PVC, set gitRepositoryStorage.externalPVC.enabled to true and give the name of the PVC under

Storage for Logs

The logs can be stored in a dedicated persistent volume. This volume has to be a read-write-many volume to be able to be used by multiple pods.

logStorage.enabledWhether to enable persistence of logsfalse
logStorage.externalPVC.useWhether to use a PVC deployed outside the chartfalse
logStorage.externalPVC.nameName of the external PVCgerrit-logs-pvc
logStorage.sizeSize of the volume5Gi
logStorage.cleanup.enabledWhether to regularly delete old logsfalse
logStorage.cleanup.scheduleCron schedule defining when to run the cleanup job0 0 * * *
logStorage.cleanup.retentionDaysNumber of days to retain the logs14
logStorage.cleanup.resourcesResources the container is allowed to userequests.cpu: 100m
logStorage.cleanup.additionalPodLabelsAdditional labels for pods{}
requests.memory: 256Mi
limits.cpu: 100m
limits.memory: 256Mi

Each pod will create a separate folder for its logs, allowing to trace logs to the respective pods.

CA certificate

Some application may require TLS verification. If the default CA built into the containers is not enough a custom CA certificate can be given to the deployment. Note, that Gerrit will require its CA in a JKS keytore, which is described below.

caCertCA certificate for TLS verification (if not set, the default will be used)None


ingress.enabledWhether to enable the Ingressfalse
ingress.hostREQUIRED: Host name to use for the Ingress (required for Ingress)nil
ingress.additionalAnnotationsAdditional annotations for the Ingressnil
ingress.tls.enabledWhether to enable TLS termination in the Ingressfalse
ingress.tls.secret.createWhether to create a TLS-secrettrue
ingress.tls.secret.nameName of an external secret that will be used as a TLS-secretnil
ingress.tls.certPublic SSL server certificate-----BEGIN CERTIFICATE-----
ingress.tls.keyPrivate SSL server certificate-----BEGIN RSA PRIVATE KEY-----
For graceful shutdown to work with an ingress, the ingress controller has to be configured to gracefully close the connections as well.

Git garbage collection

gitGC.imageImage name of the Git-GC container imagek8sgerrit/git-gc
gitGC.scheduleCron-formatted schedule with which to run Git garbage collection0 6,18 * * *
gitGC.resourcesConfigure the amount of resources the pod requests/is allowedrequests.cpu: 100m
requests.memory: 256Mi
limits.cpu: 100m
limits.memory: 256Mi
gitGC.logging.persistence.enabledWhether to persist logstrue
gitGC.logging.persistence.sizeStorage size for persisted logs1Gi
gitGC.tolerationsTaints and tolerations work together to ensure that pods are not scheduled onto inappropriate nodes. For more information, please refer to the following documents. Taints and Tolerations[]
gitGC.nodeSelectorAssigns a Pod to the specified Nodes. For more information, please refer to the following documents. Assign Pods to Nodes. Assigning Pods to Nodes{}
gitGC.affinityAssigns a Pod to the specified Nodes. For more information, please refer to the following documents. Assign Pods to Nodes using Node Affinity. Assigning Pods to Nodes{}
gitGC.additionalPodLabelsAdditional labels for Pods{}


The way the Jetty servlet used by Gerrit works, the Gerrit component of the gerrit chart actually requires the URL to be known, when the chart is installed. The suggested way to do that is to use the provided Ingress resource. This requires that a URL is available and that the DNS is configured to point the URL to the IP of the node the Ingress controller is running on!
Setting the canonical web URL in the gerrit.config to the host used for the Ingress is mandatory, if access to Gerrit is required!
While the chart allows to configure multiple replica for the Gerrit StatefulSet, scaling of Gerrit is currently not supported, since no mechanism to guarantee a consistent state is currently in place. This is planned to be implemented in the future.
gerrit.images.gerritInitImage name of the Gerrit init container imagek8sgerrit/gerrit-init
gerrit.images.gerritImage name of the Gerrit container imagek8sgerrit/gerrit
gerrit.tolerationsTaints and tolerations work together to ensure that pods are not scheduled onto inappropriate nodes. For more information, please refer to the following documents. Taints and Tolerations[]
gerrit.topologySpreadConstraintsControl how Pods are spread across your cluster among failure-domains. For more information, please refer to the following documents. Pod Topology Spread Constraints{}
gerrit.nodeSelectorAssigns a Pod to the specified Nodes. For more information, please refer to the following documents. Assign Pods to Nodes. Assigning Pods to Nodes{}
gerrit.affinityAssigns a Pod to the specified Nodes. For more information, please refer to the following documents. Assign Pods to Nodes using Node Affinity. Assigning Pods to Nodes{}
gerrit.additionalAnnotationsAdditional annotations for the Pods{}
gerrit.additionalPodLabelsAdditional labels for Pods{}
gerrit.replicasNumber of replica pods to deploy1
gerrit.updatePartitionOrdinal at which to start updating pods. Pods with a lower ordinal will not be updated.0
gerrit.resourcesConfigure the amount of resources the pod requests/is allowedrequests.cpu: 1
requests.memory: 5Gi
limits.cpu: 1
limits.memory: 6Gi
gerrit.persistence.enabledWhether to persist the Gerrit sitetrue
gerrit.persistence.sizeStorage size for persisted Gerrit site10Gi
gerrit.livenessProbeConfiguration of the liveness probe timings{initialDelaySeconds: 30, periodSeconds: 5}
gerrit.readinessProbeConfiguration of the readiness probe timings{initialDelaySeconds: 5, periodSeconds: 1}
gerrit.startupProbeConfiguration of the startup probe timings{initialDelaySeconds: 10, periodSeconds: 5}
gerrit.gracefulStopTimeoutTime in seconds Kubernetes will wait until killing the pod during termination (has to be longer then Gerrit's httpd.gracefulStopTimeout to allow graceful shutdown of Gerrit)90
gerrit.networkPolicy.ingressCustom ingress-network policy for gerrit podsnil
gerrit.networkPolicy.egressCustom egress-network policy for gerrit podsnil
gerrit.service.additionalAnnotationsAdditional annotations for the Service{}
gerrit.service.loadBalancerSourceRangesThe list of allowed IPs for the Service[]
gerrit.service.typeWhich kind of Service to deployNodePort
gerrit.service.externalTrafficPolicySpecify how traffic from external is handledCluster
gerrit.service.http.portPort over which to expose HTTP80
gerrit.service.ssh.enabledWhether to enable SSHfalse
gerrit.service.ssh.portPort over which to expose SSH29418
gerrit.keystorebase64-encoded Java keystore (cat keystore.jks | base64) to be used by Gerrit, when using SSLnil
gerrit.index.typeIndex type used by Gerrit (either lucene or elasticsearch)lucene
gerrit.pluginManagement.pluginsList of Gerrit plugins to install[]
gerrit.pluginManagement.plugins[0].nameName of pluginnil
gerrit.pluginManagement.plugins[0].urlDownload url of plugin. If given the plugin will be downloaded, otherwise it will be installed from the gerrit.war-file.nil
gerrit.pluginManagement.plugins[0].sha1SHA1 sum of plugin jar used to ensure file integrity and version (optional)nil
gerrit.pluginManagement.plugins[0].installAsLibraryWhether the plugin should be symlinked to the lib-dir in the Gerrit site.nil
gerrit.pluginManagement.libsList of Gerrit library modules to install[]
gerrit.pluginManagement.libs[0].nameName of the lib modulenil
gerrit.pluginManagement.libs[0].urlDownload url of lib module.nil
gerrit.pluginManagement.libs[0].sha1SHA1 sum of plugin jar used to ensure file integrity and versionnil
gerrit.pluginManagement.cache.enabledWhether to cache downloaded pluginsfalse
gerrit.pluginManagement.cache.sizeSize of the volume used to store cached plugins1Gi
gerrit.priorityClassNameName of the PriorityClass to apply to the master podnil
gerrit.etc.configMap of config files (e.g. gerrit.config) that will be mounted to $GERRIT_SITE/etcby a ConfigMap{gerrit.config: ..., replication.config: ...}see here
gerrit.etc.secretMap of config files (e.g. secure.config) that will be mounted to $GERRIT_SITE/etcby a Secret{secure.config: ...} see here
gerrit.additionalConfigMapsAllows to mount additional ConfigMaps into a subdirectory of $SITE/data[]
gerrit.additionalConfigMaps[*].nameName of the ConfigMapnil
gerrit.additionalConfigMaps[*].subDirSubdirectory under $SITE/data into which the files should be symlinkednil
gerrit.additionalConfigMaps[*].dataData of the ConfigMap. If not set, ConfigMap has to be created manuallynil

Gerrit config files

The gerrit chart provides a ConfigMap containing the configuration files used by Gerrit, e.g. gerrit.config and a Secret containing sensitive configuration like the secure.config to configure the Gerrit installation in the Gerrit component. The content of the config files can be set in the values.yaml under the keys gerrit.etc.config and gerrit.etc.secret respectively. The key has to be the filename (eg. gerrit.config) and the file's contents the value. This way an arbitrary number of configuration files can be loaded into the $GERRIT_SITE/etc-directory, e.g. for plugins. All configuration options for Gerrit are described in detail in the official documentation of Gerrit. Some options however have to be set in a specified way for Gerrit to work as intended with the chart:

  • gerrit.basePath

    Path to the directory containing the repositories. The chart mounts this directory from a persistent volume to /var/gerrit/git in the container. For Gerrit to find the correct directory, this has to be set to git.

  • gerrit.serverId

    In Gerrit-version higher than 2.14 Gerrit needs a server ID, which is used by NoteDB. Gerrit would usually generate a random ID on startup, but since the gerrit.config file is read only, when mounted as a ConfigMap this fails. Thus the server ID has to be set manually!

  • gerrit.canonicalWebUrl

    The canonical web URL has to be set to the Ingress host.

  • httpd.listenURL

    This has to be set to proxy-http://*:8080/ or proxy-https://*:8080, depending of TLS is enabled in the Ingress or not, otherwise the Jetty servlet will run into an endless redirect loop.

  • httpd.gracefulStopTimeout / sshd.gracefulStopTimeout

    To enable graceful shutdown of the embedded jetty server and SSHD, a timeout has to be set with this option. This will be the maximum time, Gerrit will wait for HTTP requests to finish before shutdown.

  • container.user

    The technical user in the Gerrit container is called gerrit. Thus, this value is required to be gerrit.

  • container.javaHome

    This has to be set to /usr/lib/jvm/java-11-openjdk-amd64, since this is the path of the Java installation in the container.

  • container.javaOptions

    The maximum heap size has to be set. And its value has to be lower than the memory resource limit set for the container (e.g. -Xmx4g). In your calculation, allow memory for other components running in the container.

To enable liveness- and readiness probes, the healthcheck plugin will be installed by default. Note, that by configuring to use a packaged or downloaded version of the healthcheck plugin, the configured version will take precedence over the default version. The plugin is by default configured to disable the querychanges and auth healthchecks, since these would not work on a new and empty Gerrit server. The default configuration can be overwritten by adding the healthcheck.config file as a key-value pair to gerrit.etc.config as for every other configuration.

SSH keys should be configured via the helm-chart using the gerrit.etc.secret map. Gerrit will create its own keys, if none are present in the site, but if multiple Gerrit pods are running, each Gerrit instance would have its own keys. Users accessing Gerrit via a load balancer would get issues due to changing host keys.

Installing Gerrit plugins

There are several different ways to install plugins for Gerrit:

  • RECOMMENDED: Package the plugins to install into the WAR-file containing Gerrit. This method provides the most stable way to install plugins, but requires to use a custom built gerrit-war file and container images, if plugins are required that are not part of the official release.war-file.

  • Download and cache plugins. The chart supports downloading the plugin files and to cache them in a separate volume, that is shared between Gerrit-pods. SHA1- sums are used to validate plugin-files and versions.

  • Download plugins, but do not cache them. This should only be used during development to save resources (the shared volume). Each pod will download the plugin-files on its own. Pods will fail to start up, if the download-URL is not valid anymore at some point in time.

Upgrading the Chart

To upgrade an existing installation of the gerrit chart, e.g. to install a newer chart version or to use an updated custom values.yaml-file, execute the following command:

cd $(git rev-parse --show-toplevel)/helm-charts
helm upgrade \
  <release-name> \
  ./gerrit \ # path to chart
  -f <path-to-custom-values>.yaml

Uninstalling the Chart

To delete the chart from the cluster, use:

helm delete <release-name>