Building a Windows Server 2008 Cluster, Part 2
Feb 9, 2009 / By Edwin Sarmiento
In Part 1 of this series, we prepared our Windows Server 2008 servers to be a part of a cluster. In this part, we will look at adding the iSCSI disks to the servers. The series of steps outlined below should be done on both nodes.
Before we go any further, I must mention that you should have at least two network cards configured on both of the servers, where one NIC is connected to the local area network, and the other to the other server and is private. This second NIC will be considered your heartbeat, where communication between nodes will travel. This is basic when configuring any cluster nodes. How these cards are configured will come into the picture as we go along in the process.
1. Add the iSCSI Targets as disks on the server nodes
Windows Server 2008 comes with iSCSI Initiator software that enables connection of a Windows host to an external iSCSI storage array using network adapters. This differs from previous versions of Microsoft Windows where you need to download and install this software prior to connecting to an iSCSI storage. You can launch the tool from Administrative Tools and select iSCSI Initiator.
To connect to the iSCSI target:
- In the iSCSI Initiator Properties page, click on the Discoverytab.
- Under the Target Portals section, click on the Add Portal button.
- In the Add Target Portal dialog, enter the DNS name or IP address of your iSCSI Target and click OK. If you are hosting the target on another Windows host, make sure that you have your Windows Firewall configured to enable inbound traffic to port 3260. Otherwise, this should be okay.
- Back in the iSCSI Initiator Properties page, click on the Targets tab. You should see a list of the iSCSI Targets that we have defined in Part 1 of this series.
- Select one of the targets and click on the Log on button.
- In the Log On to Target dialog, select the Automatically restore this connection when the computer starts checkbox. Click OK.
- Once you are done, you should see the status of the target change to Connected. Repeat this process for all the target disks we initially created.
Once the targets have been defined using the iSCSI Initiator tool, you can now bring the disks online, initialize them, and create new volumes using the Server Manager console. I won’t go into much detail on this process as it is similar to how we used to do it in Windows Server 2003, except for the new management console. After the disks have been initialized and volumes created, you can try logging in to the other server and verify that you can see the disks there as well. You can rescan the disks if they haven’t yet appeared.
2. Install the Windows Server 2008 Failover Cluster Feature
As Failover Clustering is not installed by default, we need to add it on both of the servers that will form a part of our cluster.
- Open the Server Manager console and select Features.
- Click the Add Features link. This will run the Add features Wizard.
- In the Select Features dialog, select the Failover Clustering checkbox, and click Next.
- In the Confirm Installation Selections dialog, click Install to confirm the selection, and proceed to do the installation of the Failover Clustering feature.
- In the Installation Results dialog, click Close. This completes the installation of the Failover Clustering feature on the first node.
Once you have completed the installation of the Failover Clustering feature, you will see a new management console under Administrative Tools; this is the Failover Cluster Management.
3. Run the Validate Cluster Configuration Wizard
Unlike in previous versions of Windows, where Microsoft had some sort of a hardware compatibility list (HCL) from which we have to find and select components tested to be clustering-supported, this wizard is like the “stamp” that tells you whether or not the hardware you are using is supported. One word of caution: do not skip any error message that this wizard generates in the final report. Doing so would simply mean that you are on your own and support from Microsoft is out of the picture. To run the Validate Cluster Configuration Wizard:
- Open the Failover Cluster Management console.
- Under the Management section, click the Validate a Configuration link. This will run the Validate a Configuration Wizard.
- In the Select Servers or a Cluster dialog, enter the hostnames of the nodes that you want to add as members of your cluster and click Next.
- In the Testing Options dialog, click Next to run all the necessary tests to validate whether or not the nodes are okay for clustering.NOTE: The first time you run them, select the Run all tests (Recommended) option. This will run all the necessary tests to check the servers that will be a part lof the cluster. Further runs can be selective tests as long as you know what you are testing. This would be appropriate when adding new hardware such as network cards or disks to the existing cluster.
- In the Confirmation dialog box, click Next. This will run all the necessary validation tests.
- In the Summary dialog box, verify that all the reports return success. Click on the View Report button to see a detailed report that was generated by the wizard.
At this point, the wizard will tell you whether or not you can proceed to the next step of creating your cluster. As I’ve previously mentioned, do not attempt to go any further if this report returned any error messages. In fact, I expect you to have errors, as most of the installations I’ve done weren’t successful, thanks to a known issue. You will see an error in the Summary Report similar to the one displayed below:
Verifying that there are no duplicate IP addresses between any pair of nodes. Found duplicate IP address fe80::100:7f:fffe%13 on node node1.domain.local adapter Local Area Connection* X and node node2.domain.local adapter Local Area Connection* X.
This has to do with the Teredo IPv6 Tunneling Protocol. To resolve this issue, follow the these steps:
- Open Command Prompt and ‘Run as Administrator’.
> netsh > interface > teredo > set state disabled
- Open Device Manager from the Server Management console.
- Under the View menu, select Show hidden devices.
- Expand Network Adapters and choose to disable the Teredo Tunneling Pseudo-Interface.
Cluster Validate Error for Duplicate IP Addresses? Teredo may be the Culprit! from Symon Perriman, Program Manager for Clustering & HA at Microsoft, recommends doing steps 1 to 2 (or even tweaking the registry). In my case, however, I needed to do steps 3 to 5 before I got a successful summary report generated by the Validate Cluster Configuration wizard.
After disabling the protocol, re-run the Validate Cluster Configuration wizard until you get a successful Failover Cluster Validation Report.
We’ve come this far to make sure that both nodes are geared up and ready for clustering. In the third part of this series, we will walk through the process of creating the cluster. You wouldn’t have read this far if you weren’t up for the challenge, right?