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New Member

SIP phone issues


I have got a very strange issue. If anyone has any idea about it please help!

We had moved from traditional isdn link to SIP and it is working fine but sometimes some of the phones cannot dial outside numbers(Mobile, 1300 and landline). On the other hand, same model phones are working fine no issues. When I checked in Cisco RTMT about why some phones with same models are working and other phones with exactly same model are not working I found that from call manager it is only sending invite messages that's it. I do not understand why this is happening. Please see below screen shot from RTMT. In perfect environment when phones are working fine it should be like this.

But when phones are not dialing out it is showing as is the CUCM and is the CUBE router.

Thank You,



New Member

Re: SIP phone issues

Please see attached RTMT output for both working and not working phones. This is the continuation of previous post.


Re: SIP phone issues

Hi Rohit,

Its look like network issue that CUBE is not able receive INVITE sent by CUCM at that moment. You need to first look at the connectivity or congestion angle between them.

Or there is one more possiblity that CUBE interface binding is not correctly placed.


Rate all the helpful post.



Re: SIP phone issues

Hi Rohit,

Do share failed call and successful call log from RTMT and CUBE as well & "show running-config" of gateway.

You can check below points from your end:

1). Are both (working & non-working) phones are in same subnet / subscriber?

2). Check the IP Address of SIP trunk configuration. It should be of CUBE internal.

3). Compare both INVITE messages.

Nishant Savalia

Regards, Nishant Savalia