Understanding MS DTC Resources in Failover Clusters

Applies To: Windows Server 2008

In Windows XP and Windows Server 2003, the Cluster Administrator tool makes the following changes to the Microsoft Distributed Transaction Coordinator (MS DTC) configuration:

  • Creates an MS DTC resource in a resource group that contains a shared disk resource and a network name resource

  • Creates an MS DTC log file on the shared disk in the MS DTC resource group so that the MS DTC transaction manager can access the MS DTC log file from any server computer in the cluster

  • Copies critical MS DTC registry entries to the shared cluster registry

  • Causes the MS DTC to run under the Network Service account by default, regardless of the account that the MS DTC ran under before it was added to the cluster. These account changes are propagated to a cluster node only when MS DTC is online on that node.

When the MS DTC is running in clustered mode, only one node in the cluster can run the MS DTC transaction manager.

Any process that runs on any node in the cluster can use the MS DTC. These processes call the MS DTC proxy in the normal way, and the MS DTC proxy automatically forwards MS DTC calls to the MS DTC transaction manager that controls the entire cluster.

Prerequisite conditions must be met before you configure the MS DTC to run in a clustered environment. For more information, see Requirements for Creating an MS DTC Resource in a Failover Cluster.

This section includes the following topics with more information about MS DTC resources and how they work in Windows Server failover clusters.