[Asterisk-Users] port number keeps changing

[Steven Critchfield]

On Mon, 2004-02-09 at 10:52, Matt Lawson wrote:
> We have an asterisk installation that's on a residential-grade DSL and 
> its port number (as visible from the outside) keeps changing, every time 
> it registers.  fuser indicates that asterisk is only using port 4569 for 
> IAX2 (as it should), but when it goes out over the Internet, the port 
> number is reported as something in the 10000's and it changes every time.
> 
> Obviously, this is a network issue of some type, but can anyone explain 
> more precisely why this happens and how to stop it?  We have some other 
> installations that stay put on port 4569 like they're supposed to. 
>  Network issues aren't my area of expertise.

Networking 101. Inbound services must stay on a specific port so as to
be known. Outbound connections can start on any port not already taken
as long as it connects to the proper known service on the other side.
This is normal operation. Watch your web browser sometime as it connects
from some random high port to remote port 80 every time.
-- 
Steven Critchfield  <critch at basesys.com>