Chapter 30. Rolling Upgrades

Procedure 30.1. Perform Rolling Upgrades Using REST

1. Configure the Target Cluster

   Use either different network settings or a different JGroups cluster name to set the Target Cluster (consisting of nodes with new JBoss Data Grid) apart from the Source Cluster. For each cache, configure a RestCacheStore with the following settings:
   1. Ensure that the host and port values point to the Source Cluster.
   2. Ensure that the path value points to the Source Cluster's REST endpoint.

2. Start the Target Cluster

   Start the Target Cluster's nodes. Configure each client to point to the Target Cluster instead of the Source Cluster. Eventually, the Target Cluster handles all requests instead of the Source Cluster. The Target Cluster then lazily loads data from the Source Cluster on demand using the RestCacheStore.

3. Dump the Key Set

   When all connections have shifted to the Target Cluster, remove the Source Cluster key set. This is done either using JMX or the CLI as follows:

   1. Using JMX

      Invoke the recordKnownGlobalKeyset operation on the RollingUpgradeManager MBean on the Source Cluster for all caches to be migrated.

   2. Using the CLI

      Run the upgrade --dumpkeys command on the Source Cluster for all caches to be migrated. Optionally, use the --all switch to dump all the caches in the cluster.

4. Fetch the Remaining Data

   The Target Cluster must fetch all the remaining data from the Source Cluster. This is done either using JMX or the CLI as follows:

   1. Using JMX

      Invoke the synchronizeData operation with the rest parameter specified on the RollingUpgradeManager MBean on the Target Cluster for all caches to be migrated.

   2. Using the CLI

      Run the upgrade --synchronize=rest on the Target Cluster for all caches to be migrated. Optionally, use the --all switch to synchronize all caches in the cluster.

5. Disable the RestCacheStore

   Disable the RestCacheStore on the Target Cluster using either JMX or the CLI as follows:

   1. Using JMX

      Invoke the disconnectSource operation with the rest parameter specified on the RollingUpgradeManager MBean on the Target Cluster.

   2. Using the CLI

      Run the upgrade --disconnectsource=rest command on the Target Cluster. Optionally, use the --all switch to disconnect all caches in the cluster.