I am a not a seasoned pro by any means, so please excuse my ignorance.
GS GXP2130, 2160, and 2170, FreePBX. phones in ring group continue to ring after call is answered, it appears to be semi-random. It doesn’t happen on every call, but often 20%-30%, some days worse than others (60%-80%)??? usually most phones in the ring group, but sometimes just one and hops from one to the other on each call. I have researched and found conflicting reasons and no solutions, so I hope someone can help solve this mystery. We have an account with this problem and they are very upset, to the point we could lose the account over it. We have tried everything, firmware different phones/models etc. I really like the GS phones, but these are the only phones that do this. We began phasing out cisco, polycom based on price/attractiveness etc, but we didn’t have this issue.
phones in ring group continue to ring after call is answered. PLEASE HELP
I have experienced events where a call comes in and rings multiple phones and then once one is answered the remaining keep ringing.
Almost every time it has been because the phone system was being overloaded by something. Usually a SIP attack of some kind.
Have you ruled this out as a possibility?
This can also be due to a low quality router that doesn’t properly handle UDP packets.
Does the problem persist if you put all the phones in TCP?
Thanks for your help! I really appreciate it.
Regarding SIP attack:
Well I think that is always a possibility. Not entirely sure I know what you mean. Is there an easy way to tell? I have seen the incessant “dead-air” calls (usually from caller id “100” or something generic), is that what you’re referring to? This is actual business related calls from real customers etc, that cause the problem.
Additional info: These phones are hosted from a main site across the WAN. 4 sites total, 3 remote. It occurs at all site far as I know. We have fail2ban running on the server and I believe all these phones have “Authenticate incoming invite” set to YES. That seemed to cure the above problem. This problem seems relatively new. I was told that the it happened once in great while on just a phone or two, then fairly recently it got increasingly worse.
Regarding router:
We don’t handle IT for this account, but I’m positive they use Cisco routers, I don’t know the exact model/version offhand, but they are the smaller PIX/ASA type. I’ll find out.
I haven’t tried any UDP/TCP changes yet.
I’ll try to get these questions answered and get back with you. Thanks Again!!!
You might want to enable keep-alive and “use random port” in those phones. That will defiantly help the router.
As mentioned before, commonly this is either the router or the server being overworked.
update: I have set up these sites with their own router/firewall, static IPs for each phone, set up one site as queue instead of ring group, etc. Unfortunately, still have the problem.
I’m out of ideas and almost out of time. Anybody have any suggestion?
You should open a ticket if you haven’t already.
I’d start looking at the entire path of the calls in packet captures and see what things are doing.
from how it enters to how it gets to the phones and track down where the signalling is dying.