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CM8.0 VG202 modem problems

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JayShoup

IS-IT--Management
Jul 7, 2006
16
0
0
US
We have several ID card readers (like credit debit card machines) that are used to transmit billing information via a modem to the state department of education. Unlike all of our credit card machines (which have been upgraded to use the Internet to transmitt data) these machines can not be upgraded and MUST use a modem for data transmission.

Our PBX is a Cisco Call manager 8x system using Cisco 2921 and a VWIC2-2 T1 card configured as 2 pri circuits to the PSTN.
All of our routers within the system are configured for MGCP and have the SRST packages installed and activated.

The card reader/modesm are connected to the system via one of two methods... either an ATA186 or a 2921 a VIC3 FXS analog port.
Up until 2 weeks ago everything "seemed" ok and i had received no complaints indicating the modems were failing. Over the last 2 weeks it has been brought to my attention that none of the 6 card machines are able to transmitt their data reliably.

All of our routers are also configured to use t38 as the fax protocol and we are having NO issues with FAX. We use an Xmedius fax server, configured H.323 to pass all inbound faxes to the fax server. Fax machines connected to the FXS analog ports of the routers are also having NO issues.

I have looked at the T1 counters and see NO SLIP errors. However, i do see:

T1 0/0/1 is up.
Applique type is Channelized T1
Cablelength is long 0db
No alarms detected.
alarm-trigger is not set
Soaking time: 3, Clearance time: 10
AIS State:Clear LOS State:Clear LOF State:Clear
Version info Firmware: 20100222, FPGA: 13, spm_count = 0
Framing is ESF, Line Code is B8ZS, Clock Source is Line.
CRC Threshold is 320. Reported from firmware is 320.
Data in current interval (651 seconds elapsed):
0 Line Code Violations, 8 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 2 Degraded Mins
6 Errored Secs, 2 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

NOTICE the errored Secs Degraded MIN..... Not sure if this is relevent to the modem passthrought issue or not.

I have noticed that in CM 2921 router connfigration pages that MODEM PASSTHROUGH is set to "ENABLE", CISCO FAX RELAY is set to "DISABLE", and T38 FAX RELAY is set to "ENABLED"... allthough, since the modem is configured MGCP rather than SCCP i am not sure if these settings matter... DO THEY?

When i look at the router configuration is see:

mgcp fax t38 ecm
mgcp fax t38 ls_redundancy 1
mgcp rtp payload-type g726r16 static
mgcp modem passthrough voip mode nse


Does anyone have any thoughts on WHY we are having problems passing modem signals to the PSTN?

PS: we have aso configured VG202's and seem to be having issues there as well....

Any thoughts?




Network Administrator - Communications & Security Services
Merrillville Commuity School Corp.
276 East 68th Place
Merrillville, IN 46910
 
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