[asterisk-users] Polycom SIP Phones On LAN can't register without WAN (Internet) Access

[Noah Miller]

Hi Shawn -

> We have several Polycom 500/501/601's on both a LAN and at employee homes.
> The problem we are having is if our internet connection goes down the Local
> LAN phones loose their connection to the Asterisk Server.
> I've checked everything I can think of but can't figure out why its
> happening.
> I believe since the Asterisk Box is on the LAN and the phones are on the
> same LAN then it shouldn't need internet to function.
>
> The closest I have narrowed this down is to the DNS area. I found that if I
> block access to our ISP's DNS that the phones aren't able to register with
> asterisk.
>
> This baffles me because the phone has the LAN address for the Asterisk
> server so I don't know why it's doing DNS lookups.

Hmm.  Well, you've got me.  I don't know why it would be doing that,
it certainly shouldn't be.  You might try a newer version of the SIP
firmware or the 3.2.2 bootrom.

If it still happens with the latest bootrom/firmware, you could do a
packet trace on the phone.  Is it doing DNS queries?  If so, I'd call
your Polycom reseller and have them take this up with Polycom (support
requests are supposed to go through the reseller).  Actually, in any
case, I'd take it up with your Polycom reseller.


- Noah