Re: pg_basebackup: return value 1: reason?

On 04/17/2016 12:13 PM, Andrej Vanek wrote:
> Hello Adrian,
>
> I tried to use -U without "su"- launched directly by root: same behaviour.
> Finally I reverted my script to use standard backup (pg_start_backup;
> rsync; pg_stop_backup)- this works- the only downside is possible
> collisions with on-line backup/synchronizaiton of other two nodes on
> master node...
>
> Back to the pg_basebackup issue: it is clear to me that this is an issue
> of environment which launched pg_basebackup.
> Possibly either some privileges or  some kernel parameters/limits. Who
> knows?
> Summary: clusterlab's crm_mon launched a shell script starting
> pg_basebackup which fails to do some its work (pg_basebackup: could not
> wait for child process: No child processes)- probably due to some
> failing system call.
>
> How can I report to clusterlabs: What system call fails in pg_basebackup?

All I can to do is point you at:

https://wiki.postgresql.org/wiki/Getting_a_stack_trace_of_a_running_PostgreSQL_backend_on_Linux/BSD

>
> Best Regards, Andrej
>
>
>
> 2016-04-17 1:09 GMT+02:00 Adrian Klaver <adrian.klaver@aklaver.com
> <mailto:adrian.klaver@aklaver.com>>:
>
>
>     Is the su - even necessary?
>
>     pg_basebackup is a Postgres client program you can specify the user
>     you want it to connect to using -U.
>
>     Or do you need the script to run as postgres in order to get
>     permissions on wherever you are creating the backup directory?
>
>         have to find out why pg_basebackup cannot fork when launched
>         from crm_mon.
>
>
>
>     I assume crm_mon is this:
>
>     http://linux.die.net/man/8/crm_mon
>
>     from Pacemaker.
>
>     I do not use Pacemaker, but I am pretty sure that running what is a
>     monitoring program in daemon mode and then shelling out to another
>     program is not workable. The docs seem to bear this out:
>
>     http://clusterlabs.org/wiki/PgSQL_Replicated_Cluster#Installation
>
>     https://github.com/smbambling/pgsql_ha_cluster/wiki/Building-A-Highly-Available-Multi-Node-PostgreSQL-Cluster
>
>


--
Adrian Klaver
adrian.klaver@aklaver.com