Microsoft has overhauled Windows Clustering Services to meet the greater demand for high availability and scalability that has come with the increased spread of the 24/7 marketplace. I'm going to discuss some of the new features that the Windows Server 2003 Clustering Services have to offer, as well as some tips for using WS2K3 clustering.
In Windows 2000, in order to use clustering services, you had to have Windows 2000 Advanced Server. The Windows Server 2003 product line is similar, as you must have either the Windows Server 2003 Enterprise Edition or Datacenter Edition.
There are three key advantages to clustering:
- Scalability: Windows Server 2003 clusters support up to eight processors (32 processors in the Datacenter Edition) and a maximum of 8 GB RAM (64 GB in the Datacenter Edition).
- Availability: A properly installed and configured cluster provides continued operation during hardware failure, software failure, and/or planned maintenance.
- Manageability: Windows Server 2003 allows administrators to manage all resources within the entire cluster from one MMC.
New in Windows Server 2003
These are some of the improvements Windows Server 2003 has made in clustering:
- Larger clusters:The Enterprise Edition now supports up to 8-node clusters. Previous editions only supported 2-node clusters. The Datacenter Edition supports 8-node clusters as well. In Windows 2000, it supported only 4-node clusters.
- 64-bit support: This feature allows clustering to take advantage of the 64-bit version of Windows Server 2003, which is especially important to being able to optimize SQL Server 2000 Enterprise Edition.
- High availability: With this update to the clustering service, the Terminal Server directory service can now be configured for failover.
- Cluster Installation Wizard: A completely redesigned wizard allows you to join and add nodes to the cluster. It also provides additional troubleshooting by allowing you to view logs and details if things go wrong. It can save you some trips to the Add/Remove Programs applet.
- MSDTC configuration: You can now configure MSDTC once and it is replicated to all nodes. You no longer have to run the comclust.exe utility on each node.
Installing the cluster
When you install Windows 2003 Server, the Cluster Administrator is installed by default. You simply need to launch the Cluster Administrator to begin configuring your cluster. You can do this by going to Start | Administrative Tools | Cluster Administrator. When installing a new cluster, you no longer have to reboot, which is a great time saver.
Also, one of the nice features in WS2K3 is that, during installation of a new cluster, you are provided with a report (see Figure A) that will help you solve any issues prior to creating the cluster. When you see this report, you can expand the + sign and choose Details to correct specific problems, or you can simply click View Log to look at all the logged information in Notepad.
Now I'm going to walk through a typical installation of a new cluster in WS2K3. I will begin by opening the Cluster Administrator from the Start Menu. Next, a drop-down menu will pop up. At this point, you should choose Create New Cluster and click OK (see Figure B).
You will now be introduced to the New Server Cluster Wizard. Click Next to proceed with the wizard. In the next window, you can select or type the name of the domain in which your cluster will be created and you can enter a name for your cluster (see Figure C).
Click Next to continue. The Select Computer window allows you to enter the machine name of the first computer in your cluster (see Figure D).
The next window will analyze your configuration and provide you with details on any issues that may arise before configuring your cluster (see Figure E).
Once you have finished analyzing your configuration, the next window is where you will enter the IP address that the clustering tools will use to connect to the cluster (see Figure F).
Next, you will enter an account name that you will use as the service account for the cluster (see Figure G).
The following window gives you a summary of your proposed configuration and lets you make any changes, if necessary. You also have the option of choosing which drive the quorum resource is placed on (see Figure H).
To continue, click Next and the cluster will be created. You will then receive a confirmation that all tasks have completed (see Figure I).
If there are errors, click the Details button to help resolve the problems. If your task completed successfully, you can now log in to your cluster from the Cluster Administrator.
In order to add additional nodes to your cluster, you simply run the wizard again and choose Add Nodes To Cluster from the drop-down menu (see Figure J).
What do you think of Windows Clustering? Are you currently using it in your shop? Please share your experiences.