Pacemaker agent for MySQL

Resource Agent for managing MySQL servers on Debian, leaving replication managing to MySQL, and system administrator.

It's very minimalistic agent - can start, stop, and check MySQL status. And even for those basic functions, it relies on /etc/init.d/mysql script. With this agent you can manage your MySQL with /etc/init.d/mysql - even when pacemaker is turned off.

No resources migration, no replication management.

To pin IP address to specific MySQL server in master-master replication, and do automatic failover.

MySQL-Debian resource position across cluster is constant, and it depends on server-id parameter configured in MySQL server. You can't migrate mysql-debian resources between nodes. So when for example MySQL die on crm1, it can't be moved to crm2. It makes no sense, because on crm2 there is second mysql-debian resource. It should be master-master replication.

• Before working with pacemaker, you need to manually create master-master replication between nodes.
• Create user for monitoring, with USAGE grant
• Set different server-id on both MySQL servers in my.cnf
• server-id in my.cnf must match with server-id in pacemaker resource

Create resources, we assume that you have 2 nodes in cluster with server ids 1 and 2 - crm1 and crm2

$ pcs resource create mysql_crm1 ocf:heartbeat:mysql-debian server_id=1 monitoruser_login=monitor monitoruser_pass=monitor123

$ pcs resource create mysql_crm2 ocf:heartbeat:mysql-debian server_id=2 monitoruser_login=monitor monitoruser_pass=monitor123

Set preferences for above resources:

$ pcs constraint location mysql_crm1 prefers crm1

$ pcs constraint location mysql_crm2 prefers crm2

Set pereference for first IP address:

$ pcs constraint colocation add mysql_vip_master with mysql_crm1 300

$ pcs constraint colocation add mysql_vip_master with mysql_crm2 250

Set preference for second IP address:

$ pcs constraint colocation add mysql_vip_slave with mysql_crm2 200

$ pcs constraint colocation add mysql_vip_slave with mysql_crm1 150