Not too bad since I spent some time figuring this out on debian etch previously: 1, 2, 3.

Get the software:
apt-get install open-iscsi multipath-tools

First, make the node chat with the MD3000i (change portal IP):
iscsiadm -m discovery –type sendtargets –portal 10.0.9.10 -P 1

Then log in to the MD3000i with MDSM, add host (manual), type in the hostname, and set up some disk mappings.

Then have the node log in to the MD3000i:
iscsiadm -m node -l

Get multipath to sort out all the disks:
multipath -ll

It will print out some business like:
sdb: checker msg is "directio checker reports path is down"
sdf: checker msg is "directio checker reports path is down"
36001e4f0003968c6000012da48aac3d1dm-0 DELL ,MD3000i
[size=278G][features=0][hwhandler=0]
\_ round-robin 0 [prio=0][enabled]
\_ 1:0:0:0 sdb 8:16 [failed][faulty]
\_ round-robin 0 [prio=1][active]
\_ 2:0:0:0 sdd 8:48 [active][ready]
\_ round-robin 0 [prio=1][enabled]
\_ 3:0:0:0 sde 8:64 [active][ready]
\_ round-robin 0 [prio=0][enabled]
\_ 4:0:0:0 sdf 8:80 [failed][faulty]
sdc: checker msg is "directio checker reports path is down"
1_dm-1 DELL ,Universal Xpor
[size=20M][features=0][hwhandler=0]
\_ round-robin 0 [prio=0][enabled]
\_ 1:0:0:31 sdc 8:32 [failed][faulty]


The third line should map to a device in /dev/mapper/, you can do whatever you want with.