From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Christie <michaelc@cs.wisc.edu>
Subject: Re: Multipath with 2 NICs?
Date: Thu, 25 Oct 2007 13:06:54 -0500
Message-ID: <4720DB3E.3090506@cs.wisc.edu>
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Scott Moseman wrote:
> We're interesting in using multipath I/O from our Red Hat servers with
> our iSCSI SAN in order to have failover in the event of a switch
> failure.  Our vendor gave me a product matrix and it says we cannot
> use 2 NICs under Red Hat, we must use 1 NIC and 1 HBA.  I'm not
> finding any clear cut explanation of this in the device-mapper
> documentation, unless I'm missing something.  Are we really required
> to use an HBA instead of just 1 NICs with DM?
> 

In RHEL 5.0, that is true.

In RHEL 5.1 you can now bind a session to a specific nic and multipath 
over the two sessions. See sectrion 5.1 in 
/usr/share/doc/iscsi-initiator-utils-*/README for info on how to do this.