Re: Patch: Implement failover on libpq connect level.

On Mon, 26 Oct 2015 16:25:57 -0400
Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:

> Also, this assumes that all the components other than host and port
> are the same. Earlier there was a discussion about why the ports
> would ever need to be different. Well, why can't the database names
> be different? I could have use for that.

Because of way postgresql replication is implemented.

This multihost feature is for clusters. Either for automatic switch
from one cluster node to another when master node fails and one of the
standbys get promoted to master, or for load balancing between hot
standby nodes.

Postgresql allows different replicas listen on different ports, because
each replica has its own postgresql conf, but repication works on the
node level, not on the database level, so all the databases from master
node would be replicated with their original names.