[cisco-voip] 3825 Voice Gateway Issue

[David Fielder (US)]

I have a very interesting issue at a client I am working with. We are
converting this customer from a Nortel to CallManager. This customer is
using IP phones already. There are four locations that are converting to
IP phones. All four locations will be using a single 3825 voice gateway
to the PSTN. We connected the phones at one location and configured the
gateway as an MGCP gateway. We have two Bellsouth ISDN PRIs connected to
the gateway that came out of the Nortel. The ISDN connections come up
with no problem. We have verified the Frame type with the Bellsouth and
the PRI are working fine. The phones are using PoE and are getting the
IP address via DHCP and are using a voice VLAN. The PCs are connected to
the access port on the phones. The Phones register to the Subscriber
just fine. Calls are being routed to the Gateway with no problem.
Inbound calls make it to the IP phones fine. So you are asking then what
the problem is. There is no audio on the call or ring back. The call
sets up fine. The ISDN debugs show no errors. The phone maintains the
connection until you hang up. And if you look at the RTP and UDP debugs
it is sending and receiving the RTP traffic without issues or appears to
be. You can start an ISDN Q931 debug and make a call. When the call is
connected look at the traffic info on the phone and everything appears
as it should accept there is no audio, static or anything. We have made
calls from different phones, phone types (7961, 7912, and IP
Communicator) with the same result. IP connectivity is good. There are
no IP routing issues. We upgraded the IOS on the Gateway. We caused the
phones to go into SRST mode to remove the CallManager from the equation
and it was the same result. Cisco to Cisco calls work great. This one
has TAC scratching there head. If anyone has ever seen a problem like
this or have any other suggestions I would really appreciate your input.

 

David Fielder

Senior Engineer

Dimension Data

Office: (336) 510-9431

Mobile: (336) 669-5129

david.fielder at us.didata.com

 




-----------------------------------------
Disclaimer:

This e-mail communication and any attachments may contain
confidential and privileged information and is for use by the
designated addressee(s) named above only.  If you are not the
intended addressee, you are hereby notified that you have received
this communication in error and that any use or reproduction of
this email or its contents is strictly prohibited and may be
unlawful.  If you have received this communication in error, please
notify us immediately by replying to this message and deleting it
from your computer. Thank you.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://puck.nether.net/pipermail/cisco-voip/attachments/20061016/b09caf59/attachment-0001.html