[Lustre-discuss] lustre file system with failover

[Kalpak Shah]

On Thu, 2008-06-26 at 21:25 -0700, Dhruv wrote:
> 
> On Jun 13, 1:53 pm, Johann Lombardi <joh... at sun.com> wrote:
> > On Wed, Jun 11, 2008 at 01:07:56PM +0100, trupti shete wrote:
> > > I am having the following scenario of lustre file system--
> > > MDT- /dev/sdc on node1 and failnode node2
> > [...]
> > > If client1 opens a file to write and at that time if I umount the MDT (which
> > > will be mounted on node1) will node2 take care of?
> >
> > Just in case it is not clear, you need to remount the mdt on node2 by hand
> > or configure an external HA software (like Heartbeat/linux-HA) to manage the
> > failover.
> 
> Is HA software compulsory? Does lustre inherently provides some
> mechanism?

Lustre filesystem only supports failover at the server level. Lustre
does not have a complete failover solution which includes failure
detection, power control, etc. So you need an external HA mechanism like
Heartbeat which can detect the failure of the primary server and control
the failover. This HA software will control Lustre with a provided
service script (which will mount the OST or MDT on the secondary node)

The link provided below should answer most of your questions about
Lustre failover:

> >
> > http://manual.lustre.org/manual/LustreManual16_HTML/Failover.html#504...
> >

Thanks,
Kalpak