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New Member

cucm 8.6 call drop

We have a new cucm cluster [pub-sub-sub] running under version 8.6 and we're currently experiencing call drops every now and then but not all the time. When we are on a call [line 1] and someone is calling us from another line [line 2] while the call is still ringing on the other line [line 2] our present call [line 1] drops or we can't hear anything from our present call. Any suggestions and recommendations are highly appreciated.

Everyone's tags (2)

cucm 8.6 call drop


There's a lot of things involved here that could cause your dropped calls. Do you have QoS enabled on your switches? Do you see any drops on the interfaces that the two phones are connected to? Is the call completely internal or is it external? If both ends of the call are using different codecs, are there enough Media Resources configured to transcode the call? Usually when one side of the call drops and the other is still active, it's a network issue because one phone is not receiving the signalling that notifies the call has ended.

I would start by looking at your network!



New Member

cucm 8.6 call drop


The problem is when making outbound calls there is a long lag or even a dropped call if an incoming call rings in while your just dialing out. QOS is already set on the router but not on the switch, already checked both codecs and media resources. I've downloaded logs using rtmt hope you can interpret it for me I can send it to you if you can.