Tuesday, 9 August 2011

Configuring Microsoft’s iSCSI Target 3.3 – Some Notes on Cluster Based Initiators

We just went through configuring an iSCSI Target setup for a three node Hyper-V Failover Cluster. Here are some thoughts on the configuration in no particular order.

iSCSI Target Name

Something to consider when connecting the cluster nodes to the iSCSI based storage is the name of the target. Only _one_ target will be used for the entire cluster. Therefore, we needed to give the target a rather generic name.

  • Cluster-VM-BU-Target

Note that the naming convention for the target is very specific.

iSCSI Software Target – IQN

When we set up the target we need to log on to each node and start the iSCSI Initiator service. On Server Core or Hyper-V Server 2008 R2:

  1. Open an elevated Command Prompt
  2. iscsicpl.exe [Enter]
  3. Click the Configuration Tab
  4. Highlight the server’s Initiator name and Copy
  5. Repeat for each node

Back on the iSCSI Software Target server we use the Advanced Identifiers dialogue when setting up the iSCSI Target to past in all of the cluster node’s IQNs.

When doing so we will be warned for each IQN beyond the first:


Microsoft iSCSI Software Target

You have assigned multiple initiators to this iSCSI target. Unless the server is in a cluster or uses a SAN file system, you should only allow one initiator access to an iSCSI target. Are you sure you want to allow multiple initiators to access this iSCSI target?

The answer is obviously yes for each prompt! :)

Once our target is configured we add the iSCSI Software Target server’s IP to the Targets tab on each node.


We then click the Auto Configure button shown above with all of the target VHDs showing up if everything is configured correctly.

iSCSI Target VHD to VM Connection

Once we have our storage configured and connected to the nodes, we initialize all of the new disks in Node 1’s Disk Management. From there we format them, give them specific names to identify them, and then set them to Offline status.

For the other nodes in the cluster we need only refresh the Disk Management view, ignore any Initialize Disk questions if requested, and then set the drives to Offline.

From there we can use Hyper-V Management to connect the iSCSI Target VHD to a specific VM via Hyper-V’s SCSI bus which is hot swap capable.

When we have all of the storage set up and set to Offline, we log onto the cluster based VM and set up the storage as needed.

iSCSI Software Target and MPIO

Now that we have all of the basic building blocks in place we will look at specific scenarios where the Microsoft iSCSI Software Target server has a number of LAN connections to serve up those targets. Introducing MPIO brings with it a level of complexity that may not be needed for our needs at this time though.

We will continue to test and work with this setup for backup targets for now.

Philip Elder
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book

*Our original iMac was stolen (previous blog post). We now have a new MacBook Pro courtesy of Vlad Mazek, owner of OWN.

Windows Live Writer

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