Re: Req. for some help with resolving the error "pg_basebackup: could not get WAL end position from server: FATAL: requested WAL segment"

Hi John,

Thank you for the feed back. Presently it is taking around 1hr to finish the backups. We have the wal_keep_segments set to 50. Is there way to adjust the segment size to be more than 16MB? At times I notice in the pg_xlog, there are 10-15 segments on an invocation point.

Thanx,
Sam

From: John Scalia [mailto:jayknowsunix(at)gmail(dot)com]
Sent: Monday, December 05, 2016 1:52 PM
To: Tharmarajah, Sam <sambavan(dot)tharmarajah(at)usask(dot)ca>
Cc: pgsql-admin(at)postgresql(dot)org
Subject: Re: [ADMIN] Req. for some help with resolving the error "pg_basebackup: could not get WAL end position from server: FATAL: requested WAL segment"

More than likely your keep_wal_segments setting is too low. How long is the pg_basebackup taking? Remember that segments are generated about every 5 minutes, so if the backup takes an hour, you need at least 12 segments stored. At 2 hours, you need 24 etc., I'd set the value to about 12.2 segments/hour of backup.
--
Jay

Sent from my iPad

On Dec 5, 2016, at 1:57 PM, Tharmarajah, Sam <sambavan(dot)tharmarajah(at)usask(dot)ca<mailto:sambavan(dot)tharmarajah(at)usask(dot)ca>> wrote:
Hi

I am a newbie to postgres. We are on postgres 9.1 running on RedHat 6. When we do the postgres backups we are noticing the following errors

pg_basebackup: could not get WAL end position from server: FATAL: requested WAL segment 000000010000020B00000040 has already been removed

But when I look into pg_xlog, I notice

000000010000020B00000040.00000118.backup

May I know how to resolve this error? Are the backups done with these errors, recoverable?

Thanks in advance for your support.

Thanx,
Sam