From the log, we see Reason 6 as the reason CUCM thinks the phone unregistered. This is ofcourse only half the story.
Reason 6 is...
"ConnectivityError - Network communication between the device and Unified CM has been interrupted. Possible causes include device power outage, network power outage, network configuration error, network delay, packet drops, and packet corruption. It is also possible to get this error if the Unified CM node is experiencing high CPU usage. Verify that the device is powered up and operating, verify that there is network connectivity between the device and Unified CM, and verify that the CPU utilization is in the safe range (you can monitor this via the CPU Pegging Alert in RTMT)."
thank you very much for your replies. I am sorry I didnt see them before, but I've had some trouble with the remake of the ciscofourms website and I couldnt find my post anymore.
Any way, that one is the only phone of that kind in CUCM, so I can not tell if it's a FIRMWARE related problem, however, if 6 confirms that is a network issue I have found a case that might exaplain what happened. Please find the links below for your reference:
The short answer is that you don't.... That isn't entirely true while at
the same time it kind of is, but for the most part you don't configure
the softkeys. You enable or disable them via TCL. Here is the long
answer. Be sure to read the whole thing or e...
Topology: IP Phone > Switches > Microsoft NPS setup to forward 802.1x
proxy to > ISE 2.1 patch 3 Authentication: EAP-TLS using Cisco MIC SANs
Phone Models 802.1X support? 802.1x flavor Addtl Comment EAP-MD5 EAP-TLS
Cisco 3905 Y Y N Cisco 6911 Y Y N Cisco ...
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