I have two IP Soundstation 4000 phones on my company network which stop responding to ARP requests after a while. This can happen mid-call and there is no indication of any problem until the SIP server (which needs to send a session refresh re-INVITE) sends the ARP requests, this fails and the call is torn down.
It is suspicious that both phones have started experiencing this problem at the same time, so it may be that there is something on the network that is exposing a problem on the phone. Investigations into what this might be are ongoing. I just thought I'd check here whether anyone else has experienced this problem.
This happened on BootROM 3.1.2 / SIP aoo 1.6.3 and still happens after upgrading to 4.1.7 / 3.1.7.
Further info - after stopping responding to ARP requests, the phone continues to respond to SIP re-INVITEs for a while (around 10 mins) then stops responding to those too. It will respond to the occasional ping (about 1 in 10) so it's not quite totally unresponsive.
I can't say I've heard of this before. Can you confirm the version of SIP and BootROM on the phones? Had the issue been occuring previously, or did it just start? And are the phones on the same subnet as the SIP server?
Also, when you're saying the phone stops responding to the ARP requets, where are you seeing that occur? If you havent already, a packet capture taken at the phone would be very useful to see exactly what the phone is sending and receiving at the time of the failure.
This happened on BootROM 3.1.2 / SIP app 1.6.3 and still happens after upgrading to 4.1.7 / 3.1.7.
The phones are on the same subnet as each other and the SIP server, though connected into different ethernet switches.
The lack of responses to ARP requests was seen in a Wireshark capture on the SIP server. I added static ARP entries on the SIP server to see what happened, and after a while the phone failed to respond to a re-INVITE anyway. It has been in this state for 4 days now - it responds to about 1 in 20 ping requests. The phone's UI is still responsive - shows correct dates, beeps on button presses etc., but cannot make or receive a call (doesn't respond to the INVITE).
The problem has apparently been happening for a while, but the phones used to be OK. While it's possible that they have both suffered some kind of simultaneous hardware failure, it is of course much more likely to be something in the environment that has changed which is provoking this problem with the phones. The SIP server and media gateway that they use have not changed lately, but it's possible on a corporate network like this that something has changed. The next step when we have a chance will be to do a capture at the phone end, and see if something unusual happens around the time the phone stops responding to ARP requests, which seems to be the first sign of something going wrong.