[GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Mike Roest
Hey Everyone, We currently have a 9.1.5 postgres cluster running using streaming replication. We have 3 nodes right now 2 - local that are setup with pacemaker for a HA master/slave set failover cluster 1 - remote as a DR. Currently we're syncing with the pretty standard routine clear

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Lonni J Friedman
On Wed, Sep 19, 2012 at 8:59 AM, Mike Roest mike.ro...@replicon.com wrote: Hey Everyone, We currently have a 9.1.5 postgres cluster running using streaming replication. We have 3 nodes right now 2 - local that are setup with pacemaker for a HA master/slave set failover cluster 1 -

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Mike Roest
Specifically what is the error? psql (9.1.5) Type help for help. postgres=# select pg_start_backup('hotbackup',true); pg_start_backup - 61/B20 (1 row) postgres=# select pg_start_backup('hotbackup',true); ERROR: a backup is already in progress HINT: Run pg_stop_backup()

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Mike Roest
Our sync script is setup to fail if the pg_start_backup fails as if it fails for some other reason the sync won't be valid as the backup_label file will be missing so the slave won't have the correct location to restart from. Originally I had gone down the road of changing the sync script such

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Mike Roest
Is there any hidden issue with this that we haven't seen. Or does anyone have suggestions as to an alternate procedure that will allow 2 slaves to sync concurrently. With some more testing I've done today I seem to have found an issue with this procedure. When the slave starts up after the

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Lonni J Friedman
Just curious, is there a reason why you can't use pg_basebackup ? On Wed, Sep 19, 2012 at 12:27 PM, Mike Roest mike.ro...@replicon.com wrote: Is there any hidden issue with this that we haven't seen. Or does anyone have suggestions as to an alternate procedure that will allow 2 slaves to

Re: [GENERAL] initial sync of multiple streaming slaves simultaneously

2012-09-19 Thread Mike Roest
Performance. On our production DB the fast-archiver transfers the datadir in about half as much time as basebackup. And since this happens on every failover (since clearing the datadir and resyncing as if from scratch also takes about half the time as a rsync of an existing datadir) --Mike On