I found the issue… Avaya phones can not handle the MWI from asterisk… So the sip_additional.conf file can not have any references to mailbox=ext@device… This causes the phone to unregister itself after 60 seconds…
So I have manually removed that line from the sip_additional.conf for each of my phones… every time I make a change in the gui, the file is regenerated and the phones unregister again…
Can anyone tell me what generates that file? I would like to remove the line that adds “mailbox=”
You must remove the mailbox using the extension settings of the GUI. Remember, you can’t edit any of the additional files directly as they are generated by FreePBX.
And just so you know, the mailbox field in FreePBX cannot be left completely blank (don’t know if that’s by design or a bug) but a single space character works just as well.
See http://freepbx.org/configuration_files which is pointed to at the top of your sip_additional.conf file. The scroll down to sip_custom_post.conf and read those directions. It explains how to add and remove lines from a pre-defined sip context.
It will still exist in the file because it was generated by Freepbx and placed into that file (no where did we say it would be removed from the file) but if you take a look at the context as it is stored in memory on asterisk you will see that it is gone.