7.14.4. Upgrading or Updating your JVM

When upgrading your JVM version or installation, care should be taken as changing the JVM will momentarily remove and replace required libraries and components which may upset the operation of Tungsten Cluster while the upgrade or update takes place.

For this reason, JVM updates or changes must be treated as an OS upgrade or event, requiring a master switch and controlled stopping of services during the update process.

A sample sequence for this in a 3-node cluster is described below:

Step Description Command host1 host2 host3
1 Initial state   Master Slave Slave
2 Stop all services on host2. stopall Master Stopped Slave
3 Update the JVM   Master Stopped Slave
4 Start all services on host2 slave. startall Master Slave Slave
5 Stop all services on host3. stopall Master Slave Stopped
6 Update the JVM   Master Slave Stopped
7 Start all services on host3 slave. startall Master Slave Slave
8 Stop all services on host1. stopall Stopped Slave Slave
9 Update the JVM   Stopped Slave Slave
10 Start all services on host1 Master. startall Master Slave Slave

The status of all services on all hosts should be checked to ensure they are running and operating as normal once the update has been completed.