/var/lock/subsys/mysql should be cleaned up by init script

[Jay Janssen]

[root@ip-10-238-195-117 mysql]# service mysql stop
Shutting down MySQL (Percona XtraDB Cluster) ERROR! MySQL (Percona XtraDB Cluster) PID file could not be found!
[root@ip-10-238-195-117 mysql]# service mysql bootstrap-pxc
Bootstrapping PXC (Percona XtraDB Cluster) ERROR! MySQL (Percona XtraDB Cluster) is not running, but lock file (/var/lock/subsys/mysql) exists

This was not an issue on previous releases.

[Raghavendra D Prabhu (raghavendra-prabhu)]

There is a bug which existed in previous versions of PXC and PS as well. It is that it (init script) doesn't check if process is already running when 'service mysql start' is done. That has been fixed now.

The lock file is left out when a previous startup has failed (wherein it touches the lock file but mysqld would have failed). The stop after that won't remove that either. The right thing here is to investigate why startup failed and then remove the lock file if everything is fine. The fact that earlier releases of PXC and PS ignored this is actually a bug since it doesn't give indication of an earlier failed startup during next start (fixed in latest PXC).

Anyways, following can be done:

a) Not to touch the lock file if startup has failed. This may break the logic which indicates the failed startup.

b) Not to fail the startup but just print to error log if lock file exists. This is fine but again may hide that.

(This is also in errata - http://www.percona.com/doc/percona-xtradb-cluster/errata.html )

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXC-1448