I am facing one issue. We have CUCM servers and IP Phones in same LAN but stills Cisco IP Phones gets unregistered for 30 to 45 seconds when phone in idle mode. And in ongoing calls, phone goes in preservation mode. This is happening with any random IP Phone.
CUCM Ver is 10.5.
Can someone help out here?
Thanks in advance.
Solved! Go to Solution.
But I don't see any errors on switchports and also desktops are connected to PC ports of IP Phones are working fine.
Most of the time IP phones works but users are facing this problem 4 5 times in day.
I have collected packet capture of Phone and I found some logs as follows.
code 10 ==The TCP connection to the Cisco Unified Communication Manager experienced a timeout error
Code 23 ==The device closed the TCP connection due to a restart command from the Cisco Unified CM
But can you tell me possibilities of why CUCM experienced a timeout error?
We found the root cause of this issue. We observed that CPU utilization of Access layer switches was more than 97% which was causing disconnection between CUCM and IP phone.
so what was the issue and what is the solution? I have this issue as well. We haven't had any issues with our system or any end points for over 4 years, but this year we are replacing switches and have two different admins managing the system with different sets of knowledge and different ways of doing the same thing. Looking for what the solution was to make it stop.
I just encountered this today, when we moved a user to a new building.
The cause, was a conflict between PoE from the switch and the VoIP phone having an external power source.
The old switch was not PoE.
Unplugging the external power and relying on PoE resolved the issue.