[Lustre-discuss] Can one node mount more than one lustre cluster?

[Malcolm Cowe]

On 15/03/2011 17:15, Brian O'Connor wrote:
> Hi,
>
> What are the constraints on a client mounting more than one lustre
> file system?
>
> I realise that a lustre cluster can have more than one file system
> configured, but can a client mount different file systems from different
> lustre clusters on the same network?;ie.
>
> Assume a Single IB fabric and two Lustre clusters with separate
> MGS/MDS/OSS. One lustre is Lincoln and the other is Washington
>
>   >list_nids
> 192.168.1.10 at o2ib
>
>   >mount -t lustre lincoln:/lustre  /lincoln
>   >mount -t lustre washington:/lustre /washinton
>
> Is this doable or should they be on separate IB fabrics
>

 From my understanding, there should only be one MGS for the entire 
environment (although as many MDTs and OSTs as are required). This is 
because clients will only communicate with exactly one MGS (and will 
communicate with the MGS of the last FS mounted) and will only receive 
updates from the MGS with which it is registered. So, in the above 
example if there is a change to the "lincoln" file system (e.g. a 
failover event, some configuration changes), clients will not receive 
notification.

There's not an issue with having multiple MGS's on a site, only with 
mounting lustre file systems from multiple "domains" on the same client, 
IIRC.

Malcolm.