[asterisk-users] multiple RTP port ranges for SIP

[Kevin P. Fleming]

Klaus Darilion wrote:

> Is Asterisk really that thumb and announces port befores testing if it
> actually can open the socket?

No.

> Usually you have other services running on the same server to (e.g. DNS
> uses UDP ports), and just specifying port=1000-1999 in rtp.conf does not
> prevent that any other process on this server uses one of these ports.
> 
> Thus, usually an application will try to open an UDP socket, and if it
> that fails, it just tries to open another one (with some logic behind).
> So, if port 1000 is already taken by another application, Asterisk
> should try to open another port.
> 
> Thus I thought that if udptl opened a port within the portrange of rtp,
> res_rtp should be able to handle this. If this is not the case, IMO it
> is a serious bug in Asterisk.

It will. However, if you are using both RTP and UDPTL and have
configured them for minimally-sized port ranges based on your expected
traffic, and also used overlapping ranges, it would be easy for calls to
fail because there are no port numbers available. Using non-overlapping
ranges will make this much less likely.

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
skype: kpfleming | jabber: kfleming at digium.com
Check us out at www.digium.com & www.asterisk.org