[Serusers] Is SER doc PSTN Gateway example incomplete/incompatible with Asterisk?

[Stefan Sayer]

Hello,

Frank Durda IV wrote:
> Okay, I can see the problem here.  The INVITE is being sent to
> the PSTN switch, but with an unreachable return IP address.
> That is, SER isn't using the return IP address for the network
> interface that the packet is being sent out on, and so the PSTN switch
> has no way to send a reply that will go anywhere useful, assuming
> it pays attention to the sender address on the UDP packet itself:
...

> 
> Arguably, the references to 192.168.200.30 in the invite itself
> are also wrong, as that address is not reachable from the
> PSTN switch, only the 10.9.193.135 address would be reachable.
> 
SER will by default send the packet from the socket it received the 
request on. So try using the right IP (10.9.193.135 in that case) at the 
asterisk box, or

> 
> So, what's the best way to get SER to do the right thing?
you can also use force_send_socket 
(force_send_socket([proto:]address[:port]) to set the outgoing socket. 
In your setup with one 'public' interface and asterisk sending to the 
other one you will actually need it.

Regards
Stefan
(who is not really talking about things he does know here)

> In our config, SER is obviously forcing this behavior (possibly a
> result of missing or excess listen or alias settings?),
> because a typical program would not encounter this issue,
> as telnet/ping run from the SER box go to the right place
> and see replies:
> ser1# telnet 10.9.193.130
> Trying 10.9.193.130...
> Connected to 10.9.193.130.
> Escape character is '^]'.
> 
> 
> This is LABXTXBR549  SP-B
> Username:
> ...
> 
> 
> Frank
> 

-- 
Stefan Sayer
VoIP Services

stefan.sayer at iptego.com
www.iptego.com

iptego GmbH
Am Borsigturm 40
13507 Berlin
Germany

Amtsgericht Charlottenburg, HRB 101010
Geschaeftsfuehrer: Alexander Hoffmann