[Stgt-devel] Multiple tgtd exporting same device.

[FUJITA Tomonori]

From: Simone Gotti <simone.gotti at gmail.com>
Subject: [Stgt-devel] Multiple tgtd exporting same device.
Date: Thu, 26 Jun 2008 23:13:27 +0200

> Hi all,
> 
> to increase the availability (and also to use in future some features
> like cluster mirror with RedHat Cluster Suite when it'll be available on
> RHEL5 or in the upstream kernel) of a iscsi target server I'd like to

I'm not sure how this configuration can increase the availability.


> export the same block devices from 2 or more machines (connected to a
> common storage). Then the iscsi initiators on other client machines will
> use dm-multipath di balance I/O and to survive the lost of one or more
> scsi target machines.

You don't need multiple tgt daemons to use dm-multipath on the
initiator side.


> I'm already doing something similar with gnbd and now I'd like to do the
> same with stgt via iscsi.

You runs multiple tgt daemons on one machine and they export the same
file to initiators?

If so, you can't do that easily because SCSI protocol is not about
only READ and WRITE commands. For example, how can tgt daemons handle
RESERVE command?