Hi list!

Today I tried to change the NAT-configuration on my Firewall to use
another port for SIP. I configured it so:

/sbin/iptables -t nat -A PREROUTING -p udp -m udp –dport 10000:10100
-j DNAT –to-destination 192.168.20.120
/sbin/iptables -t nat -A PREROUTING -p udp -m udp –dport -j DNAT –to-destination 192.168.20.120:5060

then, I tried to log on my Asterisk with my mobile phone. It works. Great!

Then I tried to call an extension I created for the tests. This
extension just play a beep, record a message and play it back.

I hear the beep and I can speak my test message, then I can just hear
a couple of seconds of my message and I get this error:

[Jun 9 07:41:56] WARNING[19374] chan_sip.c: Retransmission timeout
reached on transmission 1ec8759e5160b42b92000629ec5e4771@10.102.46.147
for seqno 993 (Critical Response) — See
https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions Packet timed out after 13569ms with no response
[Jun 9 07:41:56] WARNING[19374] chan_sip.c: Hanging up call
1ec8759e5160b42b92000629ec5e4771@10.102.46.147 – no reply to our
critical packet (see
https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions).

I’m really not sure, what can be the problem, now… I read the wiki page, but I can understand what is wrong now in a
configuration that works for days…

Have I to say Asterisk, that the NAT receive data from another port?
This is the only change in my configuration since yesterday, as all
worked…

Thanks Luca Bertoncello
(lucabert@lucabert.de)