iSCSI multipath and an 800i on Ubuntu 12.04.4 64bit Server

I am going to connect my new Drobo800i to an ubuntu 12.04.4 server. I have the two iscsi interfaces on the 800i, plus two extra gig interfaces on the server.

I have setup the following scheme:
Drobo iscsi 1 ( <> Server eth1 (
Drobo iscsi 2 ( <> Server eth2 (

I have installed open-iscsi, open-iscsi-utils and multipath-tools on the server. I will make two partitions on the 800i. One at 16 TB, and the other with the remaining space. My goal is to have both of these targets presented to the server as block devices, then mount them accordingly (i.e. /dev/sdx1 <> /folder1, /dev/sdx2 <> /folder2)

Here is where I am getting stuck. It’s easy enough to setup the drobo with multiple interfaces. What I’m wondering is how to get the server setup so that it will support the multipath setup to the drobo in case one of the interfaces goes down.