check for WAL receiver if node is hot standby

[smbambling]

trafficstars

Only check for a WAL receiver process if the node is not a Master and is a Hot Standby.

[t-matsuo]

Hi Master/Slave resource doesn't need "true". I assume that this parameter is used for active/cold standby such as split site. see https://github.com/t-matsuo/resource-agents/wiki/Resource-agent-for-postgresql-9.2-for-disaster-site

Additionally it seems that wal_receiver can run without connection of replication. So checking wal_receiver process makes little sense. I am thinking about another method to know disconnection at split site.

[smbambling]

That makes sense, In my small case test with 3 local nodes setup with a Master/Slave resource. The master never seemed to run the wal_receiver process and the logs continually had warnings in them. But I can see where this check is valid in different scenarios

[t-matsuo]

The RA shows its status as xxxx-status.

* Node pm01:
    + pgsql-status                      : HS:alone

If it shows "HS:alone", you can know that the node can't connect to Master.