Dear forum
My CUCM version 12.5 is giving me a serious headache lately. To summarize, since a few moment now some of my IP phones (model 8841 especially) go randomly in registration mode for like 15-20s and come back normally, if you are on a call, it firstly goes to preservation mode but your call kept on going and as soon as you hang up, it went to registration mode and come back normally. I initially thought the phones loose communication with the cucm but after observing the behavior while it happened, I could see the cucm available on the network and others phone at the same location working perfectly.
I tried to look it up on google and found out that I could change the security profile transport type from TCP to UDP. When I make the change and apply config it didn't take effect. I tried to create a new security profile but when I click save after creation cucm gave me an HTTP 500 error below.
Kindly help me if this happened to you before. I would also be open for any tips. where can I lookup logs to troubleshoot these behaviors !?
Thanks in advance for your contribution.
