The Microsoft iSCSI initiator can be tricky to configure because there are so many options. More and more people are going to start using it because Windows Server 2012 now includes a built-in iSCSI target. Coupled together with the new Storage Spaces feature and you can build a low cost iSCSI SAN suitable for test environments or light workloads. I still recommend medium-sized companies to rely on enterprise-class storage solutions so that they have hardware support when spindles and controllers fail. I’ve attempted to save money too many times and have been burnt by low cost storage options before. At first it seems like an easy fix but later it becomes a serious problem to support a string of USB drives =)

Should you use MPIO or MCS? Did you know you cannot mix and match them?
This excellent white paper discusses design and I highly recommend it.

ISCSI Users Guide – Microsoft Corporation – Download Center

I recently configured a two-node SQL Cluster to connect to a single controller NetApp SAN. The customer did not configure it active/active so it was not possible to configure multiple paths to the iSCSI target for redundancy. So the configuration I went with was very simple but effectively load balanced storage traffic across two separate network cards that were placed on a dedicated VLAN for storage traffic.

1. Launch iSCSI Initiator
(At this point make sure the iSCSI target has authorized this particular iSCSI initiator to connect)

2. On the Discovery tab, click Discover Portal

3. Type in the IP address of your iSCSI Target

4. Go to the Targets Tab and click on the discovered target that has a status of Inactive. Click Connect

5. Leave ‘Enable Multi-path’ unchecked as we are going to use MCS instead of Multi-Path
6. Click Advanced and specify the source and target

7. Back on the main Targets page click Properties

8.  Then click MCS


9. Click Add

10. Click Advanced

11. Specify one of your iSCSI NIC’s as the initiator


12. Click OK

13. Repeat steps 9 through 12 for as many iSCSI NIC’s you have.

14. You can test this configuration by opening Task Manager and on the Networking Tab, observe the percentage usage on each iSCSI NIC while you copy a file to the LUN. They should be fairly equal.