[ClusterLabs] I want to have some resource monitored and based on that make an acton. Is it possible?

[Strahil Nikolov]

On March 10, 2020 7:31:27 PM GMT+02:00, Roman Hershkovich <warpik at gmail.com> wrote:
>I have 2 DB servers (master/slave with replica) and 2 APP servers.
>2 APP servers managed by pacemaker  (active/passive) , but i want also
>to
>monitor "which DB is master".  I can't use VIP (which could be sticked
>on
>master DB) - it is very limited virtual environment.
>
>Is it possible to create a rule or some other scenario, so in case if
>master moved - pacemaker will restart APP (app does not support
>failover) ?

Hi Roman,

If you set an order rule that  starts  first the master  and then the app, during a failover  the app will be stoped  and once the master  is switched  (slave is promoted) the  app will be started again.

Also you can consider  a  colocation rule that all  apps are  started  where  the master  DB is running  -  so the lattency will be minimal.

Best Regards,
Strahil Nikolov