The Distributed Transaction Coordinator (MSDTC) service coordinates transactions that are distributed across multiple computers and resource managers, such as databases, message queues, and file systems. This service is necessary if transactional components are to be configured through COM+. It is also required for transactional queues in Message Queuing (also known as MSMQ) and SQL Server operations that span multiple computers.
If this service stops, transactions that use this service are not performed. Clustered installations of Microsoft Exchange, SQL Server, or other applications that make use of transaction services may be affected if this service stops.
This service is installed by default and its startup type is Manual. When the Distributed Transaction Coordinator service is started in its default configuration, it logs on by using the Network Service account.
This service is dependent upon the following system components:
- Remote Procedure Call (RPC)
- DCOM Server Process Launcher
- RPC Endpoint Mapper
- Security Accounts Manager
This service is available on a Server Core installation of Windows Server 2008 R2 in addition to the Standard, Enterprise, and Datacenter editions of Windows Server 2008 and Windows Server 2008 R2.
The following table identifies the application protocols, network protocols, and ports used by the Distributed Transaction Coordinator service:
| Application protocol | Network protocol | Ports |
|---|---|---|
| RPC | TCP | 135 |
| Randomly allocated high TCP ports | TCP | random port number between 1024 – 65535 |