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<DIV><FONT face=Arial size=2>Hello, </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>latetly i got a bit confused while playing
with rtpproxy. It is said that it supports nat clients with symmetric nat.
As i know, linux is also symmetric by default. Now i get into situation where my
natted clients work for voice, but does not for fax. I traced that my
nat does not forward incomming T38 stream saying "destination
unreachable (port unreachable)". After looking at
ip_conntrack during audio call i see: </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>udp 17 180
src=192.168.0.46 dst=my.rtpproxy.ip sport=4004 dport=19006 src=my.rtpproxy.ip
dst=my.external.ip sport=19006 dport=1024 [ASSURED]
use=1<BR>udp 17 29 src=192.168.0.46
dst=my.rtpproxy.ip sport=4005 dport=19007 [UNREPLIED] src=my.rtpproxy.ip
dst=my.external.ip sport=19007 dport=4005
use=1<BR>udp 17 171 src=192.168.0.46
dst=my.rtpproxy.ip sport=5069 dport=5060 src=my.rtpproxy.ip dst=my.external.ip
sport=5060 dport=5069 [ASSURED] use=1<BR></FONT></DIV>
<DIV><FONT face=Arial size=2>but looking at first line it doesn't seem like
symmetric nat, it is clear that packets out of my.external.ip goes with low
(1024) sports. Should it be like so or my linux masquarading is misconfigured?
This audio session work ok for some reasons unknown to me. Can anyone
explain the behaviour? </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>From second line we can see that packect can't
reach 4005 port. Similar problem prevents me from receiving t38 stream i
guess. How do you configure your linux natting for set up with
rtpproxy?</FONT><FONT face=Arial size=2></DIV></FONT>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Antanas</FONT></DIV>
<DIV><FONT face=Arial size=2>NTT </FONT></DIV>
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