CS1000B - One way comms on digi and analogue

[riscyrich]

Wonder if anyone can shed some light on this for me:

I have a CS1000B that every so often only gives one way comms on the digi and analogue sets attached to the system i.e. when on site I can hear the far end but they can't hear me.

It's setup like this:

Card# Type
4 32Port Media Card
3 8Port Exchange Line
2 32Port Digital Card
1 16Port Analogue Card
0 SSC

Most of the phones on the site are i2002 or i2004's which are registered to our CS1000E so no problem with them. The CS1000B has Vtrnks onto network which don't appear to have any problems so I'm thinking it's either the media card or the ethernet interface (the little silver one on the back of the cab) but I'm not sure how to start diagnosing the fault.

One way to solve it I have found is to xsl the switch which is all well and good, but I'm not really fixing the fault. Any help would be much appreciated.

Thanks in advance.

Richard

 

[riscyrich]

Done a bit more diggin' and it seems that both the ELAN and TLAN ethernet interfaces on the MC are not responding to ping.

I'm thinking the media adaptor on the back of the cab now ? ?

R

 

[johnpoole]

if all pings are down, one way would not be the problem

(the little silver one on the back of the cab)

.. almost impossible for that to be one way problem,

have you had one way, analog to digial? ssc card, if it's always offsite to x, then i would go media card..

look at your network for stabality, then qos.. more then likely, if it's not the card then layer 3 or above..

layer 1 and 2 are very seldon one way "part" of the time.. if they go 2 wire, the net drops, goes from two way to dead

john poole
bellsouth business
columbia,sc

 

[Tman45]

First put a packet sniffer on your ELAN and TLAN. We have had various network scans cause issues with our PBX because the security guy forgot to 'exclude' the PBX subnets.
Most of the one way audio issues seem to be ACL related but that is only if its not working completely so it could be speed/duplex mismatch. We have had to hard set that even on Cisco to get things working properly.
And yes, it could be the Media Card (DSP resources).
Good luck.

 

[riscyrich]

Thanks for the advice so far guys.

Decided to have a trip out to site to run some tests...

We're only getting one way comms between IP and digi/analogue sets. Tried a digi to analogue test and it works perfectly. Am strongly suspecting the media card now.

I jumped on to the sig sever on site and can ping both ELAN & TLAN. Have looked at networking and that's all working alright, but still getting one way comms. Stange that it wasn't responding to pings earlier though. Haven't got equipment with me to packet sniff, with it being a data 'switch' I'll only see broadcast traffic so can't tell if I am seeing normal traffic to and from the card.

I'll keep digging...

Thanks again.

Richard

 

[Tman45]

Did you stat the media card yet? You may see some down channels. You can also try 'bouncing' some as we had some media cards where the channels would show idle but not work. Also check for lastest patch levels. There was a recent release for CS1000 on MC32S patches but I don't know if the MC32 patches would be the same - although we haven't patched our MC32 cards lately - but that is our older system and we are working on a maint contract currently.

 

[Aquahallic]

riscyrich,
In order to packet sniff correctly just grab your laptop and install wireshark. Then have your network guys make you a "Mirror Port" on the switch that mirrors the port you want to capture traffic from and plug your laptop into that port you might also want to ask them for an IP that's outside of the dhcp range (if that vlan happens to have dhcp on it) and staticly assign that IP to your laptop. Let wireshark run for a while then save out that capture and filter on VoIP packets. It's the "mirror port" that does all the magic that allows you to see more than just broadcast traffic, and if your network guys don't know what you're talking about.. then I'd say the network is probably where to start looking for your one way speech path probs.

Good Luck,
Aqua

 

[riscyrich]

Hi guys,

Sorry had to down tools as we had a wireless link down on another part of the network. Sorry should explain I am both a voice and data engineer hence I only have moderate understanding of Meridian/IPline/VX Works etc. I understand the port mirror setup it's just the switches this CS1000B is connected to doesn't support port mirroring and I didn't have a better switch to hand.

Before I left site the problem vanished and the whole cab started working normally. Strange thing is all I did was run a few checks here and there both on voice and data side of things - I changed nothing <really>

Have asked site to let me know when it occurs again and I will revisit...

ATB
Richard