Stream from SRST MoH server not being played on IP Phones

[rogelioalvez]

Hello team:

I am trying to configure my SRST router to play MoH to the IP Phones of that site, without success for the time being.

The IPmc layer is working properly, since I saw the LAN switch (between the SRST router and the phones) building the IPmc tree from the SRST LAN to the IP Phone destination LAN when the phone is put on hold.

Moreover, I also verified that these IP Phones on the site of the SRST router are playing the music just fine if it comes from CUCM itself via multicast across the WAN. So the MRG, MRGL, AudioSource, MoH server seem to be correctly configured on the CUCM side.

I need your help to start debugging the problem, and in this context I have some basic questions:

1. ¿How does the router know the TTL of MoH packets? ¿Does it inherit this information from CUCM? I have not seen any IOS command that tells it how to configure the TTL parameter. Unfortunatelly, I am not able to deploy a sniffer on the remote side to see the TTL of the packets coming out of the SRST router.

2. The following is the output of a couple of show commands in the SRST router:

VG01New# show ephone summary

Active MOH clients 0 (max 830), Media Clients 0, B-ACD Clients 0

File SampleAudioSource.wav type WAVE Media_Payload_G711Ulaw64k  160 bytes

Moh multicast on 239.239.239.231 port 16384 via 141.167.112.28 via 141.167.112.215

VG01New#show ccm-manager music-

Current active multicast sessions : 1

Multicast       RTP port   Packets       Call   Codec    Incoming

Address         number     in/out        id              Interface

===================================================================

239.239.239.231   16388   0/0              13399   g729r8  Lo0

¿Is this normal output?

3. After reading the configuration guide, I am not sure whether the MoH Server must be in a G.711 region. ¿Is this really a requirement? I am asking this because I found that the CUCM administrator has already configured the MoH Server in a G.722 region.

Any help will be greatly appreciated.

Best regards, Rogelio

[chris.mann · Accepted solution]

You have to set the moh multicast ip address on the router to be the same as what you have configured in CCM.

[rogelioalvez]

Hi Chris:

I found what the problem was! As I feared in my first note, I had to setup a custom region with G.711 relationship between the MoH resource and the regions where I wanted IPmc MoH to be played. That solved the issue.

IPmc address/port was already the same in CUCM and the SRST router.

Thank you very much for your help

Regards, Rogelio