Using Percona 5.6 and 5.7 nodes in the same cluster

[duncan9562]

Hi guys,

I have a 3 node cluster in the following setup:-

2 x nodes running percona-xtradb-cluster-server-5.6 5.6.30-25.16-1.wheezy
1 x node percona-xtradb-cluster-garbd-3.x (arbitrator voting member).

I am looking to migrate the cluster onto Debian Jessie, but also upgrade to Percona 5.7.

As this is a live cluster, I am very reluctant to upgrade the existing cluster nodes (and ultimately want to avoid as much downtime as possible).

My question is, can I join a node running Percona 5.7 into the existing cluster running Percona 5.6? I.e, build 2 new nodes running Percona 5.7, add them into the cluster, let them sync, then remove the nodes running 5.6…

Any help will be greatly appreciated.

Kind regards,

Duncan.

[krunalbauskar]

Mix-match of PXC-5.6 and PXC-5.7 is possible but there are some limitations

• PXC-5.7 can accept SST from PXC-5.6 (backward compatible but read the upgrade process here https://www.percona.com/doc/percona-xtradb-cluster/LATEST/howtos/upgrade_guide.html)
• Mix-match should be is temporary and not recommended for long-term use.
• PXC-5.7 node should not act as DONOR to PXC-5.6 node. (If mix-match is during transition only then this is rare possibility).

We recommend running all nodes with same version of PXC (including minor version).
Upgrade is short window and is supported.