How the MS DTC Handles Computer Failures

Applies To: Windows Server 2008

If a computer fails and then restarts, the Microsoft Distributed Transaction Coordinator (MS DTC) transaction manager on that computer—or all MS DTC resources in a failover cluster node if the computer is part of a failover cluster—normally determine the outcome of all in-doubt transactions. The following list shows the actions that the transaction manager typically takes after a failure:

• For transactions for which it was the commit coordinator, the transaction manager reads its log file to determine the outcome.

• For incoming transactions from other systems, the transaction manager reads the MS DTC log file to determine whether it was previously notified of the outcome of the transaction.

• For incoming transactions that remain in doubt, the transaction manager queries the incoming transaction manager to learn the outcome of the transaction.

• For queries from other transaction managers regarding in-doubt outgoing transactions, the transaction manager determines the outcome of each in-doubt transaction and, when it is asked, tells the resource managers that outcome. This behavior is similar to the protocol that transaction managers and resource managers follow when a computer restarts.