Thread: repmgr and archive_mode
Hi, In the repmgr README, it suggests configuration should include: archive_mode = on archive_command = 'cd .' Could someone explain why we need archive_mode enabled? In my own testing of Pg's streaming replication, I've found it to work without this enabled. Cheers, Toby
On Fri, Jul 29, 2011 at 1:42 PM, Toby Corkindale <toby.corkindale@strategicdata.com.au> wrote:
Hi,
In the repmgr README, it suggests configuration should include:
archive_mode = on
archive_command = 'cd .'
Could someone explain why we need archive_mode enabled? In my own testing of Pg's streaming replication, I've found it to work without this enabled.
AFAIK, enabling 'archive_mode' parameter turns the cluster into Archive-log Mode and generates a copy of WAL segements to ARCHIVE destination.
Strange to know that Streaming replication done without this parameter, could you share the output of the below command in the PRIMARY cluster.
show archive_mode
show archive_command
On Friday, July 29, 2011 1:23:55 am Raghavendra wrote: > On Fri, Jul 29, 2011 at 1:42 PM, Toby Corkindale < > > toby.corkindale@strategicdata.com.au> wrote: > > Hi, > > In the repmgr README, it suggests configuration should include: > > > > archive_mode = on > > archive_command = 'cd .' > > > > Could someone explain why we need archive_mode enabled? In my own testing > > of Pg's streaming replication, I've found it to work without this > > enabled. > > AFAIK, enabling 'archive_mode' parameter turns the cluster into Archive-log > Mode and generates a copy of WAL segements to ARCHIVE destination. > > Strange to know that Streaming replication done without this parameter, > could you share the output of the below command in the PRIMARY cluster. Not really, it just means that the WAL segments are not stored once they leave the the primary. Think of it as a |. > > show archive_mode > show archive_command > > --- > Regards, > Raghavendra > EnterpriseDB Corporation > Blog: http://raghavt.blogspot.com/ -- Adrian Klaver adrian.klaver@gmail.com
On Fri, Jul 29, 2011 at 3:12 AM, Toby Corkindale <toby.corkindale@strategicdata.com.au> wrote: > Hi, > In the repmgr README, it suggests configuration should include: > > archive_mode = on > archive_command = 'cd .' > > Could someone explain why we need archive_mode enabled? In my own testing of > Pg's streaming replication, I've found it to work without this enabled. > it's not really needed but in some situations you could want to archive wal segments (for example if you want to shut down the standby without having to put a really big value in wal_keep_segments) and while archive_command can be changed at anytime just reloading archive_mode needs to restart the server. so this is just a good configuration for 24x7 setups -- Jaime Casanova www.2ndQuadrant.com Professional PostgreSQL: Soporte 24x7 y capacitación
----- Original Message ----- > <toby.corkindale@strategicdata.com.au> wrote: > > Hi, > > In the repmgr README, it suggests configuration should include: > > > > archive_mode = on > > archive_command = 'cd .' > > > > Could someone explain why we need archive_mode enabled? In my own > > testing of > > Pg's streaming replication, I've found it to work without this > > enabled. > > > > it's not really needed but in some situations you could want to > archive wal segments (for example if you want to shut down the standby > without having to put a really big value in wal_keep_segments) and > while archive_command can be changed at anytime just reloading > archive_mode needs to restart the server. so this is just a good > configuration for 24x7 setups Aaah.. now that explains it perfectly. Many thanks for clearing that up! I hadn't realised that you could only change one of the two options on the fly. Thanks, Toby
On Sat, Jul 30, 2011 at 7:57 AM, Toby Corkindale <toby.corkindale@strategicdata.com.au> wrote: > Many thanks for clearing that up! I hadn't realised that you could only change one of the two options on the fly. The streaming rep options require a restart also... -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services