Polycom UC 4.x Unreachable

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Asterisk Users 2 Comments

Hello, We’ve had dozens of Polycom 3.x firmware phones deployed and working great for years. Now I’ve finally been charged with the long-overdue task of figuring out why newer Polycom devices with 4.x firmware register fine but do not respond to SIP OPTIONS request and therefore always become UNREACHABLE if the sip qualify setting is set to yes.

To my dismay, searches for solutions from others who have encountered this problem have given zero results.


2 thoughts on - Polycom UC 4.x Unreachable

  • Solved it!
    Turns out UCS Polycoms are quite picky about blank callerids, to the extant they ignore those packets completely. My global “callerid=” in sip.conf was intentionally blank. In ten years, in never caused a problem. By setting to 0, the Polycoms that didn’t respond to SIP OPTIONS (nor the NOTIFY for waiting messages) now work fine.

    If anyone is curious, the problem is easily reproduced in the dialplan by setting the callerid there to blank, then the UCS polycom will ignore that INVITE as well. Set the callerid to anything else and it’ll ring.