[Beowulf] how cluster's storage can be flexible/expandable?

[Tim Cutts]

On 12 Nov 2012, at 03:50, Duke Nguyen <duke.lists at gmx.com> wrote:

> On 11/9/12 7:26 PM, Bogdan Costescu wrote:
>> On Fri, Nov 9, 2012 at 7:19 AM, Christopher Samuel
>> <samuel at unimelb.edu.au> wrote:
>>> So JBODs with LVM on top and XFS on top of that could be resized on
>>> the fly.  You can do the same with ext[34] as well (from memory).
> 
> We also thought of using LVM on top of RAID disks, but never think of 
> XFS. Why do we need XFS and how does this compare with GPFS?

XFS is not a parallel filesystem like GPFS, but a lot of us use it because it's so easy to grow the filesystem.  I frequently do this with virtual machines to expand their storage.

1)  Add new virtual disk
2)  Scan SCSI buses in Linux
3)  pvcreate the new device
4)  vgextend
5)  lvextend
6)  xfs_growfs

Job done.

On systems in our data centre, we tend to use XFS for most local filesystems, unless we have a good reason to use something else. 

Tim

-- 
 The Wellcome Trust Sanger Institute is operated by Genome Research 
 Limited, a charity registered in England with number 1021457 and a 
 company registered in England with number 2742969, whose registered 
 office is 215 Euston Road, London, NW1 2BE.