This article applies to Domain Time II.

Last updated: 5/23/2002

Question

How can you specify the source port for DT2, NTP, or TIME/ITP?

Answer

By default, Domain Time II will use any available port as the source port when sending requests. The first free port is assigned by the operating system at the time of the request. You may, however, force Domain Time II to use a specific port instead. The following registry entries control the source port used for Domain Time II, NTP/SNTP, and TIME/ITP on Server, Full Client, and Thin Client.
• Send Port DT2
  REG_DWORD
  Default: 0 (or not present)

• Send Port NTP
  REG_DWORD
  Default: 0 (or not present)

• Send Port TIME
  REG_DWORD
  Default: 0 (or not present)

By default, these entries are not present or set to zero. When the value is not present or zero, the system will use any available port. When the value is any other number (1 to 65535) the system will try to use the port you specify. Changes take effect immediately.

Note that you cannot specify a port that is already in use by Domain Time or another process. For example, Domain Time II is always listening on port 9909, so you cannot also send requests on port 9909. Likewise, any machine running a web server is listening on port 80, so you cannot send requests from port 80.

If Domain Time cannot obtain ownership of the port you specify, it will continue operating using the first free port provided by the operating system. If Domain Time can obtain ownership, it will use the port you specify for the duration of the request, and then release it for use by other programs or the next Domain Time request.