[Lustre-discuss] forced umount of OST in failover case?

[Erich Focht]

Thanks very much for the clarification! The improvement of the manual
as proposed by Andreas makes things easier to understand.

Best regards,
Erich

On Montag 19 Mai 2008, Nathaniel Rutman wrote:
> Erich Focht wrote:
> > Hi,
> >
> > the lustre manual says:
> >
> >  2.2.1.5 Stopping a Server
> >  To stop a server:
> >  $ umount -f /mnt/test/ost0
> >  The '-f' flag means "force"; force the server to stop WITHOUT RECOVERY. 
> >  Without the '-f' flag, "failover" is
> >  implied, meaning the next time the server is started it goes through the 
> >  recovery procedure.
> >
> > So we were tempted to use "umount -f" when doing a failover of OSTs, but we
> > see problems (I/O errors on clients) during the failover when doing this.
> > Without the "-f" flag we get no I/O errors.
> >   
> yes.  That is the difference between "forced" or not.  Forced means stop 
> with errors for clients, unforced means take more time and do recovery 
> at restart.
> > Is there a recommended way of dealing with the umount at failover?
> >   
> Don't use -f
> > Best regards,
> > Erich