You can fail-over using iSCSI multi-pathing. Have the initiator log in to both targets and then setup dm-multipath to do fail-over. On the target side you could use drbd with multi primaries and there you have it, redundant storage with easy fail-over.

-Ross

-----Original Message----- From: centos-bounces@centos.org centos-bounces@centos.org To: CentOS mailing list centos@centos.org Sent: Wed Jan 02 20:15:58 2008 Subject: Re: [CentOS] Xen, GFS, GNBD and DRBD?

On 03/01/2008, at 9:55 AM, Ross S. W. Walker wrote:

Take a look at iSCSI for the storage servers. iSCSI Enterprise Target is what I use here and it works well for us.

You don't really need shared filesystems if you are doing direct block io to LVs or raw partitions as the Xen migration will handle the hand-off, but you will if you are using flat files, because of this I recommend using LVs or raw partitions as clustered filesystems will put a serious overhead on the Xen guest io.

-Ross

Ross,

I can use DRBD to mirror data between the two storage servers and iSCSI to export the block devices, but how will iSCSI cope with failure of one storage server?

Can I use heartbeat and CRM to failover the host IP and iSCSI target to the other storage server?

Regards, Tom _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos

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