[cisco-voip] Call terminated while leaving voicemail

Mike Armstrong mfa at crec.ifas.ufl.edu
Tue Mar 1 17:35:53 EST 2005


Here's the solution to our problem, FWIW: It turns out that a Unity Registry 
key (RTPPortBase) somehow (sinister forces, maybe) got set to zero. As the 
name implies, this appears to be a base address for Unity to use to assign 
UDP ports to incoming RTP streams. This value is incremented by 2 for each 
new stream, until RTPPortBase+28 has been used, at which point the cycle 
starts over again at RTPPortBase. (All this is guesswork on my part, gleaned 
from examining Ethereal traces. I suspect this value may be different in 
larger installations.) Thus, in our case, every 14th message failed, since 
Port 0 is apparently ignored or otherwise invalid. I have no idea how 
RTPPortBase came to be set to 0, or how long it's been that way. TAC advised 
setting it to 0x5910; that fixed the problem.

Mike

----- Original Message ----- 
From: "Kevin Thorngren" <kevint at cisco.com>
To: "Mike Armstrong" <mfa at crec.ifas.ufl.edu>
Cc: <cisco-voip at puck.nether.net>
Sent: Thursday, February 17, 2005 8:32 AM
Subject: Re: [cisco-voip] Call terminated while leaving voicemail


> Hi Mike,
>
> Yes you can try to use Netmon but once the buffer fills it stops saving to 
> the capture buffer.  You will probably want to capture more than just RTP 
> streams., ie, the SCCP signaling, so you can easily pick out the call and 
> see what is happening.  Setting up Netmon capture filters is a pain to put 
> it politely (at least I haven't found an easy way to do this).  I only use 
> Netmon for quick captures or if there is no other alternative.  Plus it is 
> best to compare the AudioStat information with a source outside of the 
> Unity server just in case there is a problem with the network layer in the 
> server.
>
> I would recommend setting up Sniffer or Ethereal to log to multiple files 
> (10 MB or so in size).  This way you can capture everything and not worry 
> about running out of buffer space.  Then when the problem occurs you can 
> get to it at your leisure.
>
> Kevin
> On Feb 17, 2005, at 8:05 AM, Mike Armstrong wrote:
>
>> That's what it looks like to me as well.  The Unity server isn't really 
>> all that busy, so I can just run the Microsoft Network Monitor with a 
>> large buffer and hope that I can snag a failed call.  The problem, of 
>> course, is realizing that a call has failed in time to do something about 
>> it.  I'm not familiar with the packet structure -- is there any filtering 
>> I can apply to limit the amount of data collected?
>>
>> Mike
>> ----- Original Message ----- From: "Kevin Thorngren" <kevint at cisco.com>
>> To: "Mike Armstrong" <mfa at crec.ifas.ufl.edu>
>> Cc: <cisco-voip at puck.nether.net>
>> Sent: Wednesday, February 16, 2005 9:13 PM
>> Subject: Re: [cisco-voip] Call terminated while leaving voicemail
>>
>>
>>> Hi Mike,
>>>
>>> This may be a one way audio issue.  You can try using the AudioStat tool 
>>> that is in the Tools Depot to log the calls.  It may provide you with a 
>>> quick reference to find the calls that did not record.  Of course a 
>>> packet capture of the Unity server when the problem happens will provide 
>>> a great deal of information.  This will help you to see if the audio is 
>>> making it to the server to determine if the problem is in the network or 
>>> with the server itself.
>>>
>>> My question about "perceived disconnect" is to get a better 
>>> understanding of the issue.  Sometimes the users say the call was 
>>> disconnected but in reality the call is still up but due to what the 
>>> user experiences the feel the call was disconnected.  This is good to 
>>> know but is hard to define.
>>>
>>> Kevin
>>>
>>> On Feb 16, 2005, at 4:21 PM, Mike Armstrong wrote:
>>>
>>>> I finally found a credible witness; a summary of everything I know now 
>>>> is: Unity interrupts the caller with the normal end-of-message prompt 
>>>> ("To send this messsage, Press 1...").  Pressing 1 results in no 
>>>> message in the recipient's inbox, so Unity is apparently not seeing any 
>>>> audio. The CDR shows an origCallTerminationOnBehalfOf code of 12, 
>>>> indicating the caller hung up.  No error messages appear in any event 
>>>> logs on Unity or any CallManagers.  This happens with on-net calls. 
>>>> This also accounts for several complaints I've gotten saying a caller 
>>>> claimed to have left a message, but  no message appeared in the 
>>>> client's inbox.  I'm off to TAC, I think.
>>>>
>>>> ----- Original Message ----- From: "Kevin Thorngren" <kevint at cisco.com>
>>>> To: "Mike Armstrong" <mfa at crec.ifas.ufl.edu>
>>>> Cc: <cisco-voip at puck.nether.net>
>>>> Sent: Wednesday, February 16, 2005 7:32 AM
>>>> Subject: Re: [cisco-voip] Call terminated while leaving voicemail
>>>>
>>>>
>>>>> Hi Mike,
>>>>>
>>>>> I just re-read your problem description.  Are you saying that the PSTN 
>>>>> caller is actually being hung up on by the GW or does the caller 
>>>>> perceive being disconnected?
>>>>>
>>>>> Make sure you look at detailed CCM traces too.  It could have 
>>>>> something to do with the media negotiation when the call is forwarded 
>>>>> to voicemail.
>>>>>
>>>>> Kevin
>>>>> On Feb 16, 2005, at 6:01 AM, Mike Armstrong wrote:
>>>>>
>>>>>> I had a vague recollection last night that our previous problem was 
>>>>>> an issue
>>>>>> with the TSP.  We upgraded Unity to 4.4(4) with CCM 3.3(3), and had 
>>>>>> to
>>>>>> revert from 7.0.4 to 7.0.3b.  (Case 600614122, toward the end.)  In 
>>>>>> that
>>>>>> case, the failure occured on all calls.  Now it's intermittent.  I'll 
>>>>>> check
>>>>>> the logs, and I've enabled tracing, so will wait watchfully and try 
>>>>>> to
>>>>>> collect some data.  I think it's TAC-time.
>>>>>>
>>>>>> mike
>>>>>>
>>>>>> Date: Tue, 15 Feb 2005 19:34:52 -0500
>>>>>> From: Kevin Thorngren <kevint at cisco.com>
>>>>>> Subject: Re: [cisco-voip] Call terminated while leaving voicemail
>>>>>> To: "Mike Armstrong" <mfa at crec.ifas.ufl.edu>
>>>>>> Cc: cisco-voip at puck.nether.net
>>>>>> Message-ID: <92CD9289-7FB2-11D9-A952-000A95ACADA8 at cisco.com>
>>>>>> Content-Type: text/plain; charset=US-ASCII; format=flowed
>>>>>>
>>>>>> Hi Mike,
>>>>>>
>>>>>> Sounds like this may be a one way audio issue between the GW and 
>>>>>> Unity.
>>>>>>
>>>>>> HTH,
>>>>>> Kevin
>>>>>> On Feb 15, 2005, at 5:00 PM, Mike Armstrong wrote:
>>>>>>
>>>>>>> Several users are complaining that callers trying to leave voicemail
>>>>>>> are
>>>>>>> being disconnected about 5 seconds into leaving the message. 
>>>>>>> Happens
>>>>>>> mostly
>>>>>>> when the call originates out on the PSTN, but one intra-cluster (all
>>>>>>> LAN)
>>>>>>> occurence has been reported.  I'm pretty sure I've seen this before,
>>>>>>> but
>>>>>>> can't find a specific reference to cause or cure.  Haven't got any
>>>>>>> trace
>>>>>>> data yet because the CDR recording state on the Subscriber reverted 
>>>>>>> to
>>>>>>> False
>>>>>>> when we upgraded to CCM 4.1(2), but I've shut that barn door so may 
>>>>>>> at
>>>>>>> least
>>>>>>> have some data shortly.  In the meantime, if anyone has any 
>>>>>>> thoughts,
>>>>>>> I'd
>>>>>>> love to hear them.  CCM 4.1(2), Unity 4.0(4)/Exchange 2003.
>>>>>>>
>>>>>>> Mike Armstrong
>>>>>>> UF/IFAS CREC
>>>>>>> Lake Alfred, FL
>>>>>>
>>>>>> _______________________________________________
>>>>>> cisco-voip mailing list
>>>>>> cisco-voip at puck.nether.net
>>>>>> https://puck.nether.net/mailman/listinfo/cisco-voip
>> 



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