Failover Clustering Dependencies (64-bit)
This topic applies only to SQL Server 2000 (64-bit).
There are several products that interact with Microsoft® SQL Server™ 2000 (64-bit) failover clustering. To ensure that your failover cluster functions properly, you need to understand the underlying dependencies that failover clustering has on other products.
Microsoft Distributed Transaction Coordinator (MS DTC)
SQL Server 2000 (64-bit) requires Microsoft Distributed Transaction Coordinator (MS DTC) in the cluster for distributed queries and two-phase commit transactions, as well as for some replication functionality. After you install the 64-bit versions of the Windows® Server 2003 family, and configure your cluster, you must configure MS DTC to work in a cluster by using the Cluster Administrator. Using the Cluster Administrator, go to New/Resource, and create the MS DTC resource. It is recommended that the MS DTC resource not be in the cluster group.
Running MS DTC in Clustered Mode
When MS DTC is running in clustered mode, you can create only one MS DTC resource on the entire cluster.
Any process running on any node in the cluster can use MS DTC. These processes simply call the MS DTC Proxy and the MS DTC Proxy automatically forwards MS DTC calls to the MS DTC transaction manager that is controlling the entire cluster.
If the node running the MS DTC transaction manager fails, the MS DTC transaction manager is automatically restarted on another node in the cluster. The newly restarted MS DTC transaction manager reads the MS DTC log file on the shared cluster disk to determine the outcome of pending and recently completed transactions. Resource managers reconnect to the MS DTC transaction manager and perform recovery to determine the outcome of pending transactions. Applications reconnect to MS DTC so they can initiate new transactions.
For example, suppose the MS DTC transaction manager is active on system B. The application program and resource manager on system A call the MS DTC proxy. The MS DTC proxy on system A forwards all MS DTC calls to the MS DTC transaction manager on system B.
If system B fails, the MS DTC transaction manager on system A will take over. It will read the entire MS DTC log file on the shared cluster disk, perform recovery, and then serve as the transaction manager for the entire cluster.
Note The MS DTC transaction manager, MS DTC Proxy, and Component Services administrative tools are installed on each node of a the 64-bit versions of the Windows Server 2003 family cluster. The cluster uses Microsoft Cluster Services (MSCS) as part of the setup of the 64-bit versions of the Windows Server 2003 family.
To manually install MS DTC on the 64-bit versions of the Windows Server 2003 family (running MSCS)
- Install the 64-bit versions of the Windows Server 2003 family on each node in the cluster.
- Select Start, point to Programs, point to Administrative Tools, and then click Cluster Administrator.
- In the left pane, select the name of the cluster.
- Right-click, and then click the Create Group menu item. This creates a new group in the cluster.
For more information about using MS DTC in a cluster configuration, see your Windows documentation.