adding sip.mcast.net to multicast group debian stretch

[microsystems]

We just installed a new 3cx with the latest iso from the download site. We used the custom option to allow us to install GNOME as the client requested it.

When all done, we noticed PNP was not working, so first thing we did was a netstat -g and there was no sip.mcast.net bound to the ethernet interface.

I opened an incident with 3cx, but the came back with a lame canned response that I should use Debian and OS issues not supported by them.

Anybody know the command to add sip.mcast.net to the ipv4 group membership for my interface, enp2s0 ?

my only other option is to back the 3cx up, format the HD, and install with the 3cx standard install

IPv6/IPv4 Group Memberships
Interface RefCnt Group
--------------- ------ ---------------------
lo 1 all-systems.mcast.net
enp2s0 1 239.255.255.250
enp2s0 1 224.0.0.251
enp2s0 1 all-systems.mcast.net
lo 1 ip6-allnodes
lo 1 ff01::1
enp2s0 1 ff02::fb
enp2s0 1 ff02::1:ff08:25c6
enp2s0 1 ip6-allnodes
enp2s0 1 ff01::1

 

[microsystems]

Interesting that nobody from 3cx responded to this. further testing shows that the sip.mcast.net entry as shown with netstat -g is NOT a stock Debian entry, but appears after the 3cx configuration tool is run and will actually come out of the table if you uninstall 3cx. 3cx support gives me the run around and tells me if I want a GUI ( which is why i did a custom install of Debian Stretch with GNOME) I should run windows ( you know, the one that updates whether you have live calls processing or not every few days with a reboot ). it seems my question as posed is more of a 3cx scripting issue than a OS issue, which they cannot support.
All I really want is an answer to my question, what linux command will join sip.mcast.net to the ethernet adapters multicast group, so I know for future installs. Support seems more concerned with my forbidden use of a GUI on Debian than real world supporting a customer that wants to use PNP phones that depend on multicast.

Andreas, or Nicky do you know the answer?

-end of rant-

 

[microsystems]

update, running the firewall checker seems to put this entry back in the multicast membership group. But when the system reboots it goes missing again. web research is very thin on this subject, as Debian has implemented a few new commands, for example ip replaces ifconfig, etc.

 

[NickD_3CX]

That is not how multicast groups work, you can't add it as a command as far as I'm aware, in order for it to appear, an application must have bound this socket for multicast, then it appears.

Not that that's explained, the 3CX service that does this is 3CXPhoneSystem01 (the SIP Server). This would also explain why when you run the firewall checker, which stops the services and restarts then once done, puts the entry back. You would get the same effect simply restarting all 3CX services or just the SIP Server.

Coming to your "forbidden" GUI, we have no way of knowing what it does on boot and how it affects the multicast groups. From your description (run firewall checker and starts working) we can determine that the 3CX SIP Server does add this when it starts as it should, but why not when the machine boots? It could be literally thousands of things and we can't check the compatibility with every single package available to Linux.

My suggestion giving the case would be to do a fresh install w/o GNOME and see if it works. Then install GNOME and see if it still works. Then you will have your answer. In the event that it does not work w/o GNOME, that is something that the 3CX support team can and will look into.
When we were designing the Linux version, our focus was not on the Linux GUI, contrary our recommendation is to have a dedicated Linux machine just for 3CX. For most actions, you will never have to see the command line again, you would just use the 3CX Management Console interface.

 

[microsystems]

Thank you very much for the explanation. I suspected it was a programatic call to bind to the ethernet adapter, but as i said thinly documented. Hats off to the 3cx developers for implementing this in code.
I think i have learned my lesson and will not offer GUI on Linux any more as you are correct, the interactions between programs are very unpredictable. We are also not offering windows 10 based 3cx installs any more due to the constant windows updates. We tend to do some file transfers to the 3cxpbx directory for custom templates but have standardized on Bitvise for graphical file transfers to the Linux file system.

I do appreciate you answering my quesitons and I really like the terminal emulator built into the 3cx console. Please pass along seasons greetings to the 3cx staff. I belive Vince G. from Tampa will be visiting you and I am instructing him to buy you a Holiday drink on me!

regards,

jeff
Microsystems Development