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VG204 for modem use


Hi all,

We have a VG204 and VG202 device setup in one of our offices that we've recently deployed Cisco voice services to as part of a larger rollout company-wide.  I've setup a number of these analog gateway devices for fax machine usage and they all work just fine.  Problem I am running into is that the VG204 that we've just setup in this office doesn't seem to work when the local team is trying to dial in and out via the modems they have in a server in this location.  

When the user tries to dial out via their server's modems to a customer's device (in this case Port Authority out of band management devices) they are getting "NO CARRIER" messages back.  

I have a local guy on our IT team that can do some basic testing for me so I did have him plug a plain analog phone into it and make a successful call outbound.  If I call in from my cellphone to the number assigned to one of the ports I get modem tones as expected.  So in theory I would think it should work but it doesn't.  The VG202 works just fine with faxing and the VG204 is setup just like it but I don't really know if there are some settings that should be different in these different scenarios.  Any ideas?  Anything I should do to grab some logs that might give me a clue as to what's happening?

Background info:


Gateway:  VG204

Protocol: SCCP

Settings for gateway in CUCM:

7 Replies 7

saif musa


Please try to upload the running configuration of your voice gateway vg204 here so it could be easier to identify this issue. Also what's the status of this vg204 inside CUCM. (registered, unregistered or unknown)?

Attached is the current running config.  Note:  I have redacted some bits that were confidential and/or not relevant to this discussion.

When I look at each of the 4 ports on the gateway they all show registered.  

As long as the gateway 4- ports are registered status then you don't have any issue with also the running configuration looks good. Now the question is: what you mean by (local team is trying to dial in and out via the modems they have in a server in this location). What is that server, what's the connection between vg204 and that server? 

There's a server in that location with 4 modems in it, each modem is plugged into a port on the VG204.  They are using them to dial out to customer devices offsite that have modems.  

Ok, now it's clear. Try to disconnect that server and plugs analog phone devices directly to vg204. Use those phones to dial outside the location. If they successfully dial out then the problem with the server configuration.

We did a test dial out with an analog phone, no issues.  When I dial into those numbers I get modem tones.  The server supposedly used to work before plugged into the old phone system.  Old phone system was an old 15 year old Alcatel with a few analog ports on the front.  Kind of at a loss for what could be wrong with our setup at this point.  Or I wonder if there might be something weird on the server that used to work okay with the old system but isn't happy on a Cisco setup.  


Are you sure you using the same CPtone inside both vg204 and server? It seems like you need to reformat fine tune fxs ports. Also could you debug voice ccapi inout inside cisco vg and upload the results here. The results will displayed after trying to call from and into the server. 

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