One way audio and other issues with g450

[ObLogic7]

I have been fighting an issue with dropped calls and one way audio on our Avaya CM system for a couple of days now. I am told by our phone system vendor that one way audio is an indicator of network issues (dropped packets, etc). However, all of the gateways are connected to the same switch and there are no errors or other indications of a network problem.

Sometimes when placing a call, you cannot hear anything from the other end (ringback, provider long distance code prompt, etc). After trying a few times the call will finally connect with audio.

Incoming calls are also experiencing the issue, but appear to be more along the lines of the caller cannot hear us.

Internal calls are affected by both issues.

I have had both of our carriers test the ISDN lines and they did not have anything to report. However, since internal calls are affected, I'm pretty sure this is an internal PBX/networking issue.

What I need to know is how I can proceed to identify the issue? I have done a 'display errors' command and nothing in there looks to be serious. How can I identify if it is a bandwidth issue if the gateways are connected via a single switch? Any help is appreciated.

 

[mattKnight]

Look at the switch interfaces off to the G450. That might give you some information regarding the connection. Check that the speed and duplex are correct (I tend to set the switch to be 100MB Full duplex to match the G450)

I'd also check that the ARP cache timeout on the G450 is set to s sensible (like 15 or 20 minutes) ratherthan the default 6 hours. I have had several issues where stale ARP entries have caused issues - however they usually show as a lack of dial tone when initiating a call and one way speech when receiving one

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[orypecos]

Is your comment "Internal calls are affected by both issues." saying that even calls from one internal station to another is having the same problems?

 

[ObLogic7]

@mattKnight You hit the nail on the head. It was the negotiation of the connection speed that was causing the issue. The switches were locked at 100 half-duplex with the media-gateways set to auto negotiate resulting in them negotiating a half-duplex connection to avoid collisions.

@orypecos Yes, that is what I meant. Dropped calls, one way or no audio... affected internal calls and external calls.

Thanks for the help guys. I'm a noob when it comes to phone systems and am learning as I go. With the familiarity that our vendor seemed to have with Avaya's recommendations on how to setup network links (both sides locked to the same setting or both sides auto negotiate), I am surprised that they did not find this sooner. I had to actually look at the switch and notice that the ports were in half duplex mode for them to even check what connection was being established on the media-gateway. Once I brought that to their attention, we had our networking guys correct the issue within the hour.