6.15.5. 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 Primary switch and controlled stopping/shunning 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   Primary Replica Replica
2 Shun Replica host2 datasource host2 shun Primary Shunned Replica
3 Stop all services on host2. stopall Primary Stopped Replica
4 Update the JVM   Primary Stopped Replica
5 Start all services on host2 Replica. startall Primary Replica Replica
6 Recover Replica back datasource host2 recover Primary Replica Replica
7 Ensure the Replica ( host2 ) has caught up ls Primary Replica Replica
8 Shun Replica host3 datasource host3 shun Primary Replica Shunned
9 Stop all services on host3. stopall Primary Replica Stopped
10 Update the JVM   Primary Replica Stopped
11 Start all services on host3 Replica. startall Primary Replica Replica
12 Recover Replica back datasource host3 recover Primary Replica Replica
13 Ensure the Replica ( host3 ) has caught up ls Primary Replica Replica
14 Switch Primary to host2 switch to host2 Replica Primary Replica
15 Shun host1 datasource host1 shun Shunned Primary Replica
16 Stop all services on host1. stopall Stopped Primary Replica
17 Update the JVM   Stopped Primary Replica
18 Start all services on host1 Replica. startall Replica Primary Replica
19 Recover host1 back datasource host1 recover Replica Primary Replica
20 Ensure the Replica ( host1 ) has caught up ls Replica Primary Replica
21 Switch Primary back to host1 switch to host1 Primary Replica Replica