Multi-site Upgrade from Version 8.2 to Version 9

Systems that have both persistent disk stores and a bidirectional WAN gateway to replicate data among sites can implement an upgrade that does not require system down time. It requires multiple reconfigurations during the process, so that each site can be individually upgraded while the rest of the system continues.

This procedure will not work reliably for you if any of your WAN-connected systems includes clients that use continuous queries or subscriptions. In those cases, upgrade each system separately using the procedure described in Upgrade from Version 8.2 to Version 9.

This procedure assumes that each site has already been upgraded to Pivotal GemFire version 8.2.3 or a more recent 8.2 version.

This diagram shows the initial state of the system.

The procedure for upgrading two sites, Site A and Site B:

1. Reconfigure to redirect all traffic away from Site B (which will be the first site that gets upgraded).
2. Pause the gateway senders on Site A.
3. Upgrade Site B to GemFire 9.x.
4. Start GemFire 9.x on Site B.
5. Pause the gateway senders on Site B.
6. Start the gateway senders on Site A and wait for Site A's queues to drain.
7. Once the queues have drained sufficiently, reconfigure to redirect all traffic to Site B. Site A's queues should now drain the rest of the way.
8. Upgrade Site A to GemFire 9.x.
9. Once Site A is back up, start Site B's gateway senders and wait for the queues to drain sufficiently.
10. Reconfigure to redistribute the load across both Site A and Site B.