MSDTC and firewall

Question

We are using MSDTC for SQL transactions. I am having issue with setting up firewall for MSDTC to work. The application and SQL are running on separate machine. Currently MSDTC is working if i turn off firewall on application server. I think there should be someway to add exception to the firewall setting for some ports. So that firewall can still be ON and DTC will not have any issues. I am not sure of the ports to add in firewall setting (I did try adding port 135 with no success)

Answer 1

Have your Firewall allow port 135 and the dcom port range. By default, the dcom port range is 1024-65535. Thats a big range to open up. You can limit this range in the registry or using dcomcnfg. This post describes this:

http://blogs.msdn.com/distributedservices/archive/2008/11/12/troubleshooting-msdtc-issues-with-the-dtcping-tool.aspx