SIP trunk call - no RTP message

[hiepnguyenho]

Hello everyone,

I have a problem with CUCM cluster and a SIP trunk. I have 2 Servers in cluster: CCM1 and CCM2.

- When I register IP Phone to CCM2, I can make call through SIP trunk.

- But when I register IP Phone to CCM1, I can not. I make a call to an SIP extension, it receive signal (ringing) but there's no tone on my IP Phone and both ends can not talk. When I hang up IP Phone, the other end does not end.

- I use Wireshark to analyze the flow and I see that:

     + If IP Phone registers to CCM2, there are RTP/UTP message

     + If IP Phone register to CCM1, there's no UTP/RTP

I can make sure that there's no firewall along the way between CCM1, CCM2, IP Phone, SIP PBX and SIP devices.

//CCM1 is publisher and dbreplication status is fine.

Regards,

Hiep Nguyen.

[Marcel Ammann]

Hello Hiep,

can you upload a SIP Trace of successful and an unsuccessful call?

Thank you,

Marcel Ammann

P.S.: Please rate helpful posts

[hiepnguyenho]

Well, I can not access the SIP PBX so I can not get anything from this. This is quite strange because CCM2 can make call but CCM1 does not, even they are in the same cluster.

Do we have any other thing to check?

[Brian Meade]

This must be some sort of network connectivity issues.  Are both CCM1 and CCM2 in the same subnet?

[hiepnguyenho]

Hi Brian,

CCM1, CCM2 and PBX are in 3 different subnets.

[phamvinhdat]

Test the connectivity between PBX and CUCM1, see if they can ping each other.

Dat

[hiepnguyenho]

@Dat: Yes, of course they can... I also tracert from each end.

[Brian Meade]

There must be an issue with IP connectivity then.  Check for firewalls and access-lists at every hop from  CCM1 to the SIP PBX.  You can ssh into CCM1 to do a traceroute and see where you need to check.  Make sure nothing is blocking the RTP traffic or the SIP traffic.

[Hythim Ali El Hadad]

create another SIP trunk with CCM1 ip add

wish this be helpful