Random no dial-tone on mgcp vg350

[lilljarrell]

Installing 5 new VG350,s, have 2 installed and randomly they have no dial-tone. I have practically read thru all the discussion on VG's and found this same problem using SCCP & in fact changed the In Hold-Queue to 300. I have 2 i had to put back on my old VGs, other times i can shut/no shut the voice port. Updated IOS-running newer code 15.2(4)M8. I currently use default on the voice-ports, thought i would try posting on here before opening a TAC case. 

I have opened a TAC at the beginning, I had lots of NDT, i replaced the 72FXS module, rebooted the device. Any ideas? 

Thx

[bensanden · Accepted solution]

Did you find a solution to this issue?  I've been through the same process you went through with the hold-queue modifications but still have the issue.  I have a TAC case open, but don't have a resolution yet. 

Thanks.

[lilljarrell]

Unfortunately not, can you post your response from TAC if you get one? Thx

[Peter Buijsse]

We had the same issue, the hold queue 300 in fixed the issue.

It's due to the receiving of a burst of keepalive messages.

[Andrew West]

does everything show registered

show stcapp dev summary 

WHat debugs are you running to get some help..

deb sccp packets

deb sccp events

deb sccp messages 

Those 3 should allow you to get a feel if something is causing them to drop. 

[lilljarrell]

Not running sccp so those commands are invalid, ran some various bugs that did not tell me anything, but maybe i am running the wrong bugs. I have been thinking about moving over to sccp. I do have basic configs and no configs on the ports, like do i need supervisory disconnect, etc. All the documentation gives some parameters to configure like ring & ren, but does not say they need to be configured. I just figured since running mgcp, everything handled at the UCM.

[Andrew West]

My bad..didn't see the obvious MGCP in the header.. =)

When you lose dialtone on ports , does anything show in RTMT? Any registered media sources dropping?

[lilljarrell]

I can access the RTMT, but honestly not sure how to use it. The only resources i have registered are the CUCM MTP points.

[PGE_JosephHiatt]

I have the same problem using SCCP registered ports.  About once a day I have to shut/no shut voice ports to get dialtone back.

There is not indication in CUCM or on the gateway that anything is wrong.  I have a TAC case open for over a week and I'm dumping debugs to our syslog server.  

[frank.bartolino1]

Hi all, we are having the same issue. Did you finally found a solution/workaround?

Thank you in advance for your interest!

[Peter Buijsse]

Frank,

See below. The solution is related to this bug:

CSCuo95739 - VG350 - SCCP bind to Loopback causes TCP

https://supportforums.cisco.com/discussion/12286521/vg350-sccp-ports-losing-dial-tone

[frank.bartolino1]

Hi Peter, thank you for the link. We are using MGCP on our VGs.

Anyway, the problems did not show up anymore when we were over with the cutover and we were not adding new phones on the VGs. We had the same behavior few months ago in another site. Of course the migration of analog phones on a VG 350 takes more time due to the higher port density.

Hope this could be helpful for others facing the same issues.

[PGE_JosephHiatt]

Hello,

When I was experiencing this problem, I had a multi-analog port "key system" connected to the VG350.  VG350 is running SCCP not MGCP (sorry).

The problem went away when I configured all ports on the VG350 on UCM (without DNs).  I imagine the other option is to shutdown unused voice ports on the VG350.

TAC had no idea how to fix it.

-Joseph

[lilljarrell]

The only parameter added on the voice-ports for me was the disconnect-ack option, but not sure that fixed the problem, we have not had any problems or complaints since. I dont have the ports shutdown on the VG, they just are not configured in the UCM.

[lilljarrell]

Well, i just got another port today that just has a fast busy on it. Did a shut/no shut on the VG port and reset it in call manager did not fix. I had to move the line to a different port and have the VG set to reload tonight because that seems to be the only thing that fixes these on the MGCP controlled gateway's.