Creating a failover cluster with iSCSI disks is quite simple but there is one thing you need to be sure of: support for persistent reservations by your iSCSI target. I tried to create a failover cluster with iSCSI disks served off an OpenFiler target but that did not work.

But how do you know it will not work? Well, the good thing is that Windows Server 2008 has a Cluster Validation tool that will tell you if your configuration is supported. Click the images below to see parts of the validation tool.

 

Select the servers to verify:


image 		You can select the tests to run:

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The validation tool is part of the Failover Cluster Management console that will be available to you when you install the Failover Clustering feature.

After it became clear that OpenFiler was not going to work, I switched to RocketDivision's StarWind iSCSI Target for Microsoft Windows. I downloaded the 30 days trial because the free version does not support clusters. The iSCSI target works fine with Microsoft's iSCSI Initiator in Windows Server 2008 and it supports everything that is needed to create a failover cluster.

As the iSCSI target server, I used my laptop that runs Vista. I only needed small iSCSI disks so I created file-backed iSCSI disks with the mkimage.exe tool (part of StarWind). You create a disk file with the following command:

mkimage -sparse c:\image.img 1G

After you create the disk file, you need to "publish" it so you can connect to them using iSCSI. You do this by editing the starwind.cfg file (in c:\program files\rocket division software\starwind). In the <devices> section, add the following:

<device name="ImageFile0" file="c:\image.img" asyncmode="yes" clustered="yes"/>

After you save the file, stop and start the StarWind service.

Now you can present the disk to your Windows Server 2008 servers:

  • Open Control Panel.
  • Double click the iSCSI Initator icon and answer the questions that come (to start the service etc...).
  • In iSCSI Initator properties:
    • In the Discovery tab, add the target portal (in my case, that is my Vista laptop).
    • In the Targets tab, click Refresh. You should see the iSCSI targets offered by StarWind. Click each target and click the Log on... button. Make sure you set the option to automatically restore the connection when the computer starts.
  • Close iSCSI Initiator properties (click OK).
  • In Disk Management (diskmgmt.msc) you should see an extra disk (not initialized yet)

To continue, make sure that the Failover Clustering feature is installed on each node. From Server Manager, select Features and then click Add Features. Select the Failover Clustering feature.

After installing the Failover Clustering feature, you can start Failover Cluster Management from Start / Administrative Tools. You can now create the cluster and add services and applications.

Watch out: if you do not initialize the disk, the cluster will be created as a Node Majority cluster and not as a Node and Disk Majority cluster. To create a Node and DIsk majority cluster, on one node, initialize and format the iSCSI disk as NTFS.

The screenshot below shows the management console (with some services configured). Click the image to enlarge.

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I am not showing how to create the cluster because they really made this child's play. It was not that difficult before, but now it is even simpler.

Now you have a quick and easy way to create a Windows Server 2008 cluster for testing and evaluation of the features. Have fun!