Intercom not working between Snom devices on same LAN

[Chris A]

I have 2 x Snom D717 phones I am trying to use intercom between. For whatever reason I cannot get this working anymore, as it worked at some point. Instead of intercom it calls the other extenion. The customer is unaware of when it changed unfortunately as many events have occurred since then. Both Snom D717s (extensions x101 & x111) are on the same LAN, connected to my PBX which resides in my datacenter. 3CX and phones are connected via VPN.

I ran a packet capture on both Snom phones and 3CX while trying to intercom but I am not sure what to be looking for exactly. On the source phone x101 I see the invite 100 sent to *[email protected]. I see the SIP packets showing 3CX IP ringing 180 and ok 200 to the destination phone IP (x111). I then see RTP packets between the two D717 IPs. PS I am working remote and using the web interface of the D717's to call each other and test after business hours.

Anyway to tell the difference between intercom traffic vs phone call traffic in a packet capture? Any ideas where to look for what is going on here?

 

[ChrisC_3CX]

I'd recommend the following:

• Confirm that the PBXs dial codes are in order and that there is no other dialcode set to *8 or starting with *8.
• Edit the extension making the call and go to rights, check that it has the "Can Intercom" right.

 

[Chris A]

I'd recommend the following:

• Confirm that the PBXs dial codes are in order and that there is no other dialcode set to *8 or starting with *8.
• Edit the extension making the call and go to rights, check that it has the "Can Intercom" right.

Only paging is set to *8 & the user is a member of multiple groups. One of those groups includes all extensions and the user right is set to "Can Intercom". Both extensions have user rights in this group.

 

[ChrisC_3CX]

In the Extension Group for which "Can Intercom" is enabled, make sure that the caller has the callee's extension's presence. In other words, check that:

• The caller extension has "Can see group members" enabled.
• The callee extension has "Show presence to group members" enabled.

This must be checked for the Extension Group that allows Intercom.

 

[Chris A]

So I now have the caller set as manager and the callee as a user

 

[Chris A]

I think I found what I was looking for in my packet capture, someone pointed me in the right direction. Sorry network geek here trying to see everything under the hood