5.15.3. Performing Maintenance on an Entire Dataservice

To perform maintenance on all of the machines within a dataservice, a rolling sequence of maintenance must be performed carefully on each machine in a structured way. In brief, the sequence is as follows

  1. Perform maintenance on each of the current Replicas

  2. Switch the Primary to one of the already maintained Replicas

  3. Perform maintenance on the old Primary (now in Replica state)

  4. Switch the old Primary back to be the Primary again

A more detailed sequence of steps, including the status of each datasource in the dataservice, and the commands to be performed, is shown in the table below. The table assumes a three-node dataservice (one Primary, two Replicas), but the same principles can be applied to any Primary/Replica dataservice:

Step Description Command host1 host2 host3
1 Initial state   Primary Replica Replica
2 Set maintenance policy set policy maintenance Primary Replica Replica
3 Shun Replica host2 datasource host2 shun Primary Shunned Replica
4 Perform maintenance   Primary Shunned Replica
5 Validate the host2 server configuration tpm validate Primary Shunned Replica
6 Recover the Replica host2 back datasource host2 recover Primary Replica Replica
7 Ensure the Replica ( host2 ) has caught up   Primary Replica Replica
8 Shun Replica host3 datasource host3 shun Primary Replica Shunned
9 Perform maintenance   Primary Replica Shunned
10 Validate the host3 server configuration tpm validate Primary Replica Shunned
11 Recover Replica host3 back datasource host3 recover Primary Replica Replica
12 Ensure the Replica ( host3 ) has caught up   Primary Replica Replica
13 Switch Primary to host2 switch to host2 Replica Primary Replica
14 Shun host1 datasource host1 shun Shunned Primary Replica
15 Perform maintenance   Shunned Primary Replica
16 Validate the host1 server configuration tpm validate Shunned Primary Replica
17 Recover the Replica host1 back datasource host1 recover Replica Primary Replica
18 Ensure the Replica ( host1 ) has caught up   Primary Replica Replica
19 Switch Primary back to host1 switch to host1 Primary Replica Replica
20 Set automatic policy set policy automatic Primary Replica Replica