This plugin is a Zookeeper based implementation of the Global Ref-DB interface.
It is the responsibility of the plugin to store key/pairs of the most recent sha for each specific mutable refs, by the usage of some sort of atomic Compare and Set operation. This enables a series of use-cases, including the detection of out-of-sync refs across gerrit sites. It also enables concurrent writes on a multi-master setup by enabling a shared locking mechanism for refs across multiple nodes.
Originally this code was a part of multi-site plugin but currently can be use independently.
Supported Zookeeper version is 3.5.x. For SSL connection minimal Zookeeper version is 3.5.1ZOOKEEPER-2125.
Install the zookeeper plugin into the $GERRIT_SITE/plugins directory of all the Gerrit servers that are part of the cluster.
Create the $GERRIT_SITE/etc/@PLUGIN@.config on all Gerrit servers with the following basic settings. Where zookeeperhost is the host that is running zookeeper and 2181 is the default zookeeper port, please change them accordingly:
[ref-database "zookeeper"] connectString = "zookeeperhost:2181"
For further information and supported options, refer to config documentation.