On Tue, Feb 23, 2016 at 3:09 PM, Michael Paquier <michael.paquier@xxxxxxxxx> wrote: > On Tue, Feb 23, 2016 at 6:43 AM, John Wiencek <jwiencek3@xxxxxxxxxxx> wrote: > >> I have a three node cluster using streaming replication configured as >> follows: >> One synch node and one asynch node. >> If my synch node is down the master node is hung until that node is brought >> back on line. >> >> Two questions: >> 1. Is this the expected action on my master? It makes sense if it is since >> the master is waiting for an ack from the synch node. > > Yes, when synchronous_commit = on, the default values that you should > have, the master will wait from standby the confirmation that the WAL > record for the commit has been flushed; > http://www.postgresql.org/docs/devel/static/runtime-config-replication.html#RUNTIME-CONFIG-REPLICATION-MASTER > >> 2. Is there anyway to configure my cluster so I have a synch node but not >> have my master node “HANG” if the synch node is down? > > You can do that at transaction level for example by disabling > synchronous_commit. Or you could configure both of your standbys as synchronous standbys. Only one of them will actually be a synchronous standby at a time, and the other one will take over that role if the first one is down, so your system won't hang but you'll still have the sync standby guarantee. -- Thomas Munro http://www.enterprisedb.com -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
