[Lustre-discuss] adding 2nd network to lustre

[Chris Hunter]

Is there a way to backup the configuration information on the target 
disk before changing the MGS NID (ie. adding second multi-homed network) ?

These config logs are created when the filesystem is created (ie. 
mkfs.lustre) and not regenerated each time lustre is mounted ?

To add the second network, we plan to execute the command:
tune2fs.lustre --verbose --erase-param 
--mgsnode=10.2.1.30 at o2ib,10.1.1.30 at tcp --writeconf /dev/sdb

PS It would be helpful to add this example to the manual, assuming it 
works and is non-destructive. The current example for multi-homed 
networks (mkfs.lustre) is destructive.

Thank-you in advance,

Chris Hunter


Andreas Dilger wrote:
> On Jan 09, 2009  18:31 -0500, Chris Hunter wrote:
>> Andreas Dilger wrote:
>>> On Jan 07, 2009  18:16 -0500, Chris Hunter wrote:
>>>> We currently use lustre over an infiniband network. We would like to  
>>>> allow ethernet clients (ie. no infiniband) to use the same lustre FS.
>>>>
>>>> The MDT and OSTs were all created using only the MGS infiniband   
>>>> interface (ie. mkfs.lustre --mgsnode=10.2.1.30 at ib0).
>>>>
>>>> So I am missing some configuration for the tcp network. My best guess 
>>>> we  need to use the "tunefs.lustre" command to add the mgs tcp NID to 
>>>> the  MDT. However this command won't execute while lustre is mounted.
>>>>
>>>> Any suggestions how to add the tcp network to our existing lustre ib  
>>>> network ?
>>> I believe this is documented in the Lustre manual at http://manual.lustre.org/
>> Section 7 of the operations manual does discuss multihomed lustre  
>> servers. The example given is destructive -- lustre needs to be  
>> reformatted (mkfs.lustre) for multihoming. Can we setup multihoming with  
>> our re-formating our lustre FS ?
> 
> Yes, definitely.  It should only require a --write-conf...  I think this
> has been answered previously on this list, but if not Isaac should get
> it into the manual.
> 
> Cheers, Andreas
> --
> Andreas Dilger
> Sr. Staff Engineer, Lustre Group
> Sun Microsystems of Canada, Inc.