[cisco-voip] Strange intermittent MoH problem

Wed Apr 2 03:11:56 EDT 2008

Well, theres only one CM set for multicast MoH with Mcast address
configured. I did some snooping and found something else on network
using same range as MOH Mcast range at times. So changed the CM MoH
mcast IP address and also base RTP port to something unique and not
default and we'll see what happens.

But, still doesn't explain why one would hear a unicast call from
another server while on hold. I would suspect that if 2 devices were
streaming to same mcast address and port # then the MoH may be mixed,
silent, sound like garbage, but not mixed in with another call.

So, in wait and see mode. It happens infrequently and I can't get it
to happen when I try to get it to break.

On Tue, Apr 1, 2008 at 6:01 PM, Tim Reimers <treimers at ashevillenc.gov> wrote:
>
>
>
>
> True... but there's something strange happening at the mcast layer, and it's
> GOT to be at that layer I think, given that it's:
>
>  - multiple phones
>  - multiple servers handing out the mcast streams
>  - various times
>
>  The only core area where I can see commonality in every case is the
> switching... considering what I've understood about the problem...
>
>  I shall be _most_ curious to understand what level of evil magic-user spell
> it took to accomplish this effect!
>
>
>
>  -----Original Message-----
>  From: Ryan Ratliff [mailto:rratliff at cisco.com]
>
>  Sent: Tue 4/1/2008 5:19 PM
>  To: Erick Bergquist
>  Cc: Tim Reimers; cisco-voip at puck-nether.net
>  Subject: Re: [cisco-voip] Strange intermittent MoH problem
>
>  I'll reserve judgement until a sniffer capture is done.   Even if the
>  unicast RTP stream from MP somehow made it to the wrong IP phone the
>  phone would still have to be listening on that specific RTP port for
>  the user to hear it.
>
>  -Ryan
>
>  On Apr 1, 2008, at 5:18 PM, Erick Bergquist wrote:
>  Well, The MP is using Unicast for the conference with ports in 5000
>  range on the MP side and phones are using the normal UDP RTP range.
>  The Mcast MoH is using the usual RTP port range also.
>
>  On Tue, Apr 1, 2008 at 3:35 PM, Tim Reimers
>  <treimers at ashevillenc.gov> wrote:
>  > That's what I was thinking might be happening.. same IP/port conflict
>  >  for some as-yet undetermined black magic reason....
>  >
>  >
>  >
>  >  -----Original Message-----
>  >  From: Ryan Ratliff [mailto:rratliff at cisco.com]
>  >  Sent: Tuesday, April 01, 2008 4:25 PM
>  >  To: Erick Bergquist
>  >  Cc: Tim Reimers; cisco-voip at puck-nether.net
>  >  Subject: Re: [cisco-voip] Strange intermittent MoH problem
>  >
>  >  Does MP use multicast audio for it's RTP streams?   Since each MOH
>  >  source gets its own multicast IP address/port if MP is sending
>  > multicast
>  >  for a conference (I have no idea if it does this or not) and it
>  > ends up
>  >  sending on the same IP/port the MOH server is using then this could
>  >  happen.
>  >
>  >  I'd work to get a sniffer capture so you can see what the phone is
>  >  receiving.
>  >
>  >  -Ryan
>  >
>  >  On Apr 1, 2008, at 4:26 PM, Erick Bergquist wrote:
>  >  The mcast config is normal, nothing special being done outside the
>  > norm.
>  >  IP phones hear this as well as outside callers on a H323 gateway
>  > when on
>  >  hold sometimes.
>  >
>  >  On Tue, Apr 1, 2008 at 3:13 PM, Tim Reimers
>  > <treimers at ashevillenc.gov>
>  >  wrote:
>  >> Something in the multicast configuration of the involved layer 2
>  >> devices?
>  >>
>  >>
>  >>
>  >>  -----Original Message-----
>  >>  From: cisco-voip-bounces at puck.nether.net
>  >>  [mailto:cisco-voip-bounces at puck.nether.net] On Behalf Of Erick
>  >> Bergquist
>  >>  Sent: Tuesday, April 01, 2008 4:06 PM
>  >>  To: Ryan Ratliff
>  >>  Cc: cisco-voip at puck-nether.net
>  >>  Subject: Re: [cisco-voip] Strange intermittent MoH problem
>  >>
>  >>  Both the music and the MP call, but it is clear and not cutting and
>  >> out  every second or so.
>  >>  When I've caught it happening, it seems to be calls where MoH is
>  >> playing  due to a Network Hold event (parked call, etc). I can't get
>  >> it to happen  with a user hold.
>  >>
>  >>  On Tue, Apr 1, 2008 at 2:32 PM, Ryan Ratliff <rratliff at cisco.com>
>  >> wrote:
>  >>> IP phones or PSTN calls?   Sounds like either crosstalk or a random
>  >>>  two devices using the same receive port for RTP and the stream from
>  >>> MP reaching the phone somehow.
>  >>>  Do they hear just the MP audio or both MOH and MP audio alternating
>  >>>  every second or so?   The former is crosstalk, the latter is both
>  >>> RTP
>  >>>  streams reaching the phone on the port the phone is listening on.
>  >>>
>  >>>  -Ryan
>  >>>
>  >>>
>  >>>
>  >>>  On Apr 1, 2008, at 3:07 PM, Erick Bergquist wrote:
>  >>>  Anyone ever see people on hold with Multicast MoH (Network Hold it
>  >>> appears to happen with) hear a meetingplace audio conference call
>  >>> while they are on hold? The CCM and MP are seperate servers with
>  >>> different conference bridges so I'm puzzled how the person on hold
>  >>> hears the MP conferences sometimes. It doesn't happen all the time.
>  >>> Is
>  >>
>  >>> real intermittent.
>  >>>  The Call Manager is version 4.1(3)sr4d and MeetingPlace Enterprise
>  >>  5.4.
>  >>>
>  >>>  Erick
>  >>>  _______________________________________________
>  >>>  cisco-voip mailing list
>  >>>  cisco-voip at puck.nether.net
>  >>>  https://puck.nether.net/mailman/listinfo/cisco-voip
>  >>>
>  >>>
>  >>  _______________________________________________
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>  >>  cisco-voip at puck.nether.net
>  >>  https://puck.nether.net/mailman/listinfo/cisco-voip
>  >>
>  >>
>  >
>  >
>  >
>
>
>
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