Your explanation definitely made things clearer, thank you very much, but I have a question.

Then what is the sems -d device option for? What's the difference on having one local IP or another? ( I have 2 different IPs in the same machine).

[root@pclabo modules]# sems -d eth0:1

Configuration:
       configuration file:  /usr/local/etc/sems/sems.conf
       Ser's FIFO:          /tmp/ser_fifo
       our FIFO:            /tmp/am_fifo
       plug-in path:        /usr/local/lib/sems/plug-in/
       daemon mode:         1
       local IP:            172.25.97.18

Thankyou

Llanos

>SEMS is not directly listening to any IP, it relies on the co-located instance of SER to interact with the "IP world". The topology is the following:
>
>[SER A]<--IP interface-->[SER B]<=fifo interface=>[SEMS]
>
>SER A is the standard SIP proxy, and you can configure it to forward messages to SER B as it would be another gateway (t_relay, rewrite_uri|hos, |etc..) depending on some rules (such as a predefined prefix in the r-uri as is done in the examples).
>SER B is the front end for SEMS and has a different config file from SER A. It receives the messages from SER A and forward them to SEMS using t_write_unix() so SEMS can receive the messages.
>As depicted, the interface between SER B and SEMS is not an IP interface but a FIFO or UNIX socket interface (depending on your config files).
>
>You can have SER A, SER B, and SEMS running in the same machine or place SER A in one and SER B+SEMS in another.
>
>I hope it makes things clearer,
>
>Samuel.
>
>
>Unclassified.
> >>> Llanos Serna García-Conde <llanosserna@hotmail.com> 06/01/05 01:04PM >>>
>Hi all, I have two instance of SER running, listening to the same port (5060), but to different IP addresses.
>The SER instance with ser.cfg runs in 172.25.97.19
>The SER instance with voicemail.cfg runs in 172.25.97.18
>
>SEMS is running in 172.25.97.19 and I want to change it to run in 172.25.97.18. How can I change that?
>Thanks,
>Llanos
>
>