Re: Cannot change archive_command with a reload

On 2/2/14, 9:19 AM, Raghavendra wrote:
>
>
> On Sun, Feb 2, 2014 at 9:22 PM, CS DBA <cs_dba(at)consistentstate(dot)com
> <mailto:cs_dba(at)consistentstate(dot)com>> wrote:
>
> Hi all;
>
> we have a cluster running with an archive command that is failing.
> I tried a reload and the value does not change
>
>
> Reload with new value won't work until you fix the failing
> archive_command.
>
> Eg:-
>
> ps -ef | grep arch
> postgres 29743 29736 0 Jan30 ? 00:00:00 postgres: archiver process
> failed on 00000001000000010000003D
>
> and it might cause same error you are experiencing as
>
> postgres=# select set_config('archive_command','cp %p
> /opt/PostgreSQL/9.3/a93/%f',false);
> ERROR: parameter "archive_command" cannot be changed now
>
> So, fix the archive_command first and then give new changes.
>
> Tried a set_config and I get this error:
>
> select set_config ('archive_command', 'cp %p /data/wal_tmp/%f &&
> mv /data/wal_tmp/%f /data/wal/&f', 'false');
> ERROR: parameter "archive_command" cannot be changed now
>
>
> If your archive_command pointing to "/data/wal_tmp" then please ensure
> that directory exists there. If that directory not present then
> archive process fail to copy the transaction logs. When archiver
> process in failed state you cannot apply any new changes to the
> archive_command it will fail.
>
> Also, am surprised to see "mv" command, basically the archive_command
> meant to have a copies of pg_xlogs but not any OS related directory
> movements.

we want to copy the file to /data/wal_tmp, then do a mv to /data/wal so
our process that ships a copy to the standby servers never see's a
partial file (since it watches /data/wal)

>
> Link on archive_command:
> http://www.postgresql.org/docs/9.2/static/runtime-config-wal.html
>
>
> ---
> Regards,
> Raghavendra
> EnterpriseDB Corporation
> Blog: http://raghavt.blogspot.com/
>