Re: Replication Issues

On 28/9/18 9:00 π.μ., bhargav kamineni wrote:
> Hi Team,
>
> I have configured replication using slot ,But it failed by throwing the ERROR /pg_basebackup: could not get transaction log end position from server: ERROR:  requested WAL segment
> 0000000100002C9D00000085 has already been removed /, which is  unexpected because i have created the slot on master first and then issued the base backup command from slave's end
> the command is
> /usr/lib/postgresql/9.5/bin/pg_basebackup -U  user --max-rate='150 M' --progress --verbose --write-recovery-conf --status-interval='10 s' -D data_dir  -h host_ip  -p 5433/

Either :
add  "-X stream" to the pg_basebackup command
or
increase wal_keep_segments on the server.

> These are the settings on my master
> archive_mode=on
> archive_command='/bin/true'
> wal_keep_segments=512
> max_wal_senders=4
> Series of steps i have followed :
> 1) Enabled password less authentication between master and slave
> 2)created slot on master (assuming it will store wal's regardless of other settings)
> 3)started basebackup from slave's end
> 4)Issued checkpoint at master's end
>
> Here my concern is , slave should recover WAL from replication slot but why i got the above ERROR , Why slot removed  the requested wal file , Could you please let me know the reason why it happened
> or did i miss something ?
>
> Thanks,
> Bhargav K
>

--
Achilleas Mantzios
IT DEV Lead
IT DEPT
Dynacom Tankers Mgmt