Thread: WAL log archival on standby
James Sewell,
Solutions Architect
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Hey All,Is it possible to create WAL archive files on standby servers when using streaming replication?
I know I can use archive_command or pg_receivexlog - but these will both result in me sending information to the standby servers which has already been sent via standard streaming replication. This would result in a doubling of my network traffic.
Ideally I'd prefer to conserve this bandwidth and write the files to a local archive on any active standby.
On Fri, 19 Jun 2015 13:46 Michael Paquier <michael.paquier@gmail.com> wrote:
On Fri, Jun 19, 2015 at 2:38 PM, James Sewell <james.sewell@lisasoft.com> wrote:
Hey All,
Is it possible to create WAL archive files on standby servers when using streaming replication?
Yes and no, standbys do not archive WAL in ~9.4, but you could use archive_mode = 'always' with the upcoming 9.5.
I know I can use archive_command or pg_receivexlog - but these will both result in me sending information to the standby servers which has already been sent via standard streaming replication. This would result in a doubling of my network traffic.
Ideally I'd prefer to conserve this bandwidth and write the files to a local archive on any active standby.
Both methods you mentioned are the way to go for now I am afraid, or you wait for 9.5.
I have not tried it yet but should be possible to use pg_receivexlog from the standby. If I can use standby server to create a streaming replica and with pg_basebackup it should be possible to stream wal for archiving too.
Regards
Sameer