Re: Pgsql troubleshooting & Iscsi

On 02/17/2016 09:07 AM, proj(at)free(dot)fr wrote:
> Hi everybody,
>
> I installed a postgresql database on Redhat 7.1 and I decided to move the database on an ISCSI device (LUN) inside a logical volume, mounted at starting of the machine (xfs formatted). The mounting point is /var/lib/pgsql
>
> At the boot of the server, postgresql.service is in failed status.
>
> In messages.log :
> systemd: mounting /var/lib/pgsql
> starting PostgreSQL database server
> kernel sdv: unknown partition table
> sd 2:0:0:0: [sdb] attached SCSI disk
> xfs (dm-4): Mounting V4 Filesystem
> postgresql-check-db-dir: "/var/lib/pgsql/data" is missing or empty
> postgresql.service: control process exited, code=exited status=1
> Failed to start PostgreSQL database server.
>
>
> When I'm logged on the server, if it try to start manually the database : systemctl start postgresql --> OK (and I don't lose any data, database is available)
>
> I think it's a problem of order in the boot process : network service must be started, then iscsi, then lvm etc... So I tried to force dependencies on the /usr/lib/systemd/system/postgresql.service adding "After=lvm-pgscan.service iscsi.service" etc... but the result is the same : failure in starting postgresql
>
>
>
> systemd: Starting Remote File Systems (Pre)
> systemd: Reached Remote File Systems (Pre)
> systemd: mounting /var/lib/pgsql

^ File system not mounted yet.

> systemd: starting PostgreSQL database server
> kernel sdb: unknown partition table
> postgresql-check-db-dir: "/var/lib/pgsql/data" is missing or empty

^ Cannot find mount point

> kernel: xfs (dm-4): Mounting V4 Filesystem
> postgresql.service: control process exited, code=exited status=1
> Failed to start PostgreSQL database server.
> Unit postgresql.service entered failed state
> sd 2:0:0:0: [sdb] attached SCSI disk
> starting LVM2 PV scan on device 8:16
> kernel: xfs (dm-3): Ending clean mount
> systemd: Mounted /var/lib/pgsql

^ Now file system is mounted.

> Starting Remote File Systems
> Reached target Remote File Systems
>
> Any ideas ?

Find where file system mounting is completed and start Postgres after
that. I am still figuring out systemd, so I can not offer anything more
concrete.

>
> regards,
> Magique
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com