Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

VIP Super Bronze

UCM MoH Multicast Address Ordering for Audio Sources

Today was the first time it mattered to me what multicast group address each MoH Audio Source is sending to. The MoH server specifies a starting address (e.g. 239.1.1.1) and to increment by IP Address. It appears that the base address is choosen for the highest numbered multicast-enabled audio source. For example, if UCM has two sources enabled for multicast, source one (1) will choose 239.1.1.5 while source two (2) will choose 239.1.1.1. The increment-by-five piece I understand (four available MoH codecs). This is just the address selection order that seems odd. For reference, this is 8.0.3.10000-8.

Is anyone else able to confirm this behavior? It seems backward to me but I wanted to illicit others' input before assuming it is a bug and opening a TAC case.

Please remember to rate helpful responses and identify helpful or
  • IP Telephony
1 ACCEPTED SOLUTION

Accepted Solutions
Cisco Employee

Re: UCM MoH Multicast Address Ordering for Audio Sources

Hi Jonathan,

Do you remember in which order you enabled your audio sources for multicast? The associated multicast IP address is not directly related to the audio source ID.  There is a database rule that takes the information from MOH audio source table (those that are multicast) and each multicast MOH server and updates the MOHServerMulticastInfo table with records for each audio source ID/codec/MOH Server device.  This database processing will assign multicast IP addresses in the order that the MOH audio sources are enabled for multicast.

So in your instance:  if audio source #2 was enabled for multicast befroe #1 then it received the 1st 4 multicast IP addresses and #2 received the next 4 (as the DB select shows).

Now if you disable multicast for both #1 and #2 and then reenable multicast for #1 first and enable multicast for #2 then I believe you will have the multicast IP addresses you are expecting. However  this may change if other multicast settings (MOH Server or second MOH server added) are changed.

You can check the ip address / audio source id relation easy using the below query:

run sql select * from mohservermulticastinfo

Cheers,

Kristof

1 REPLY
Cisco Employee

Re: UCM MoH Multicast Address Ordering for Audio Sources

Hi Jonathan,

Do you remember in which order you enabled your audio sources for multicast? The associated multicast IP address is not directly related to the audio source ID.  There is a database rule that takes the information from MOH audio source table (those that are multicast) and each multicast MOH server and updates the MOHServerMulticastInfo table with records for each audio source ID/codec/MOH Server device.  This database processing will assign multicast IP addresses in the order that the MOH audio sources are enabled for multicast.

So in your instance:  if audio source #2 was enabled for multicast befroe #1 then it received the 1st 4 multicast IP addresses and #2 received the next 4 (as the DB select shows).

Now if you disable multicast for both #1 and #2 and then reenable multicast for #1 first and enable multicast for #2 then I believe you will have the multicast IP addresses you are expecting. However  this may change if other multicast settings (MOH Server or second MOH server added) are changed.

You can check the ip address / audio source id relation easy using the below query:

run sql select * from mohservermulticastinfo

Cheers,

Kristof

1288
Views
5
Helpful
1
Replies
This widget could not be displayed.