[Lustre-discuss] Help needed for an upcoming HPC project

[Fegan, Joe]

> Cons: no multi-port access to disks prevents failover

Just to expand a little: Afaik, Thumper is essentially a bunch of disks
plus a single server node integrated into a fairly compact rackmount
unit. The disks are only visible to the integrated node so if that node
goes down, hangs or whatever, access to those disks is lost. To create a
Lustre configuration today that can survive the loss of a server node
you need more than one node with a physical connection to the disks, and
for that you need some sort of dual-ported scsi/sas raid box or fiber
channel san or similar.

 
-----Original Message-----
From: Andreas Dilger [mailto:adilger at sun.com] 
Sent: 22 October 2007 21:42
To: Mertol Ozyoney
Cc: lustre-discuss at clusterfs.com
Subject: Re: [Lustre-discuss] Help needed for an upcoming HPC project

On Oct 21, 2007  20:49 +0300, Mertol Ozyoney wrote:
> .         I know that some installiations have used Sun thumper
X4500's ,
> I'd like to learn pro's of cons of using Sun X4500's 

Pros: will be a good platform for ZFS, and is also very good with Linux
software RAID 5 + Lustre (used at existing sites).

Cons: no multi-port access to disks prevents failover

> .         If I use X4500 how can I provide redundancy ? What happens
if a
> node fails and how can I restore the node ?

There is currently no Lustre-level redundancy.  The Server Network
Striping
feature will replicate data at the Lustre OST level, but this will not
be
available for some time.

> .         What are the supported backup applications ? (Veritas,
legato
> etc..) Can we use incremantal backups on lustre ?

You can use any filesystem-level backup tool that runs on the clients.

I'm not sure what you mean by being able to do incremental backups, as
I'd expect that to be a function of the backup tool?

Cheers, Andreas
--
Andreas Dilger
Sr. Software Engineer, Lustre Group
Sun Microsystems of Canada, Inc.