XADM: Statically Mapped Port Limitations for Exchange Server

• Microsoft Exchange Server, versions 4.0, 5.0, 5.5

SUMMARY

This article details the limitations involved when statically mapping ports for the Exchange Server services. In particular, it is recommended that ports which fall into the ephemeral range not be assigned statically on the Exchange Server computer.

MORE INFORMATION

Ephemeral means: short-lived, or not permanent. This name is given to the port range from 1024 to 5000.

The system will assign ephemeral port numbers to processes as processes request them. If some process is using the statically assigned port when the Exchange Server service starts, the Exchange Server service will not be able to use that port later. The information store and the directory service will still register all of its other endpoints, and start successfully.

If static entries are needed for the customer's configuration, the following guidelines are recommended:

• Select ports just above 5000
  
  -or-



• Select a port number in the 4900 - 5000 range because ports are assigned from the low end of the 1024 - 5000 range first. These <<<4900- 5000?>>>ports are almost never assigned by the system even though they fall into the dynamic range.
  
  -or-



• Select ports just below 1024.
  
  NOTE: The only issue with this is the use of "well-known ports." In order to be sure the port selected below port 1024 is not in conflict with another process, is to check with RFC 1060.

Keywords :
Version : WinNT:4.0,5.0,5.5
Platform : winnt
Issue type : kbinfo