Mysql 5.7 and galera on RHEL 7 looking for equivalent for mysqld_safe --wsrep-recover

[M Jane]

Hi everyone,

I'm new to Mysql and galera and I am trying to understand crash recovery of nodes in the cluster.

I have a 3 node Galera cluster for Mysql 5.7 on RHEL7.

I have read in an old document (mysql 5.5) of a former collegue that when all three nodes have gone down, I need to determine which node was recently updated.

In order to do that I would have to run a mysqld_safe --wsrep-recover command and check te logs for the transaction id's.

Now I have been searching for the equivalent for this command with systemd but I can't seem to find it.

Is it the same as in the mysqld_bootstrap file ? Should I set the MYSQLD_OPTS to --wsrep-recover ?

Please advise

Thanks in Advance

Regards

Marian

[Saeid Bostandoust]

When all of your galera nodes down, you need to start new cluster!

Before start new cluster you need to know which node has updated database.

You need to check galera seqno number. A highest seqno number node is your next donor node in your cluster.

First start cluster on highest seqno and join other nodes to this node.

On systemd systems you need to run galera_recovery command or read grastate.dat file.