[Lustre-discuss] Network MDT possible?

[Ms. Megan Larko]

Thank you for the quick reply Brian.
Comments and clarifications in-line.

On Tue, 2008-09-23 at 16:16 -0400, Ms. Megan Larko wrote:

>> General question:  I know that a Lustre filesystem may have only one
>> MGS running in-general and only one MDS for a specific lustre
>> filesystem (for example, /usrdisk and /admin1).

>Correct.

>> Is there a way in
>> which  a Lustre filesystem may have one MGS and one MDS which runs on
>> another machine in the network?

>Sure.  There is no requirement that the MGS and MDT be in the same
>machine.

>> I have an MGS/MDS combo running right now.

>Ugh.  You really should [have] separate[d] them.  We didn't really
>intend combo mgs/mdts for more than the most simple and/or "toy"
>deployments.

Ok.   I am building a new MDS that is right now successfully on-line
using lustre-1.6.5.1
(Note: I had to use a different rpm installation order than that
recommended in the Lustre Manual page 3-4 for ver. 1.6.4 BTW.  I had
to put the kernel-ib rpm in second after the kernel-lustre-smp rpm,
then the lustre-ldiskfs, the lustre-modules and finally the lustre
rpm.)

So I could grab some hw (the requirements for an MGS-only box are low)
and create an MGS-only using the lustre-1.6.5.1.  Then I would have to
migrate my existing systems to the new set-up.  I have successfully
done file level lustre backup and restores.

Would this "upgrade" approach be better (and just put my users scratch
space on hold for a couple of weeks?

-----  small snip-----

>b.

megan