Cisco Software problem: UVM with T1 Backcard is Stuck in Yellow Alarm When Using CCS

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Would someone with the necessary technical expertise please indicate the ramifications of this problem, how widespread its impact may be (what kinds of users it would impact, sorts of problems) and whether or not it could be a y2k problem:

Cisco Software problem: UVM with T1 Backcard is Stuck in Yellow Alarm When Using CCS

January 20, 2000

The UVM (Universal Voice Module) port will return a yellow alarm to the locally connected device, usually a Private Branch eXchange (PBX) or channel bank when the UVM port receives yellow alarm. Likewise, some PBXs detect yellow alarm and return yellow alarm. This combination results in a situation where neither the UVM port nor the PBX port can be cleared from the yellow alarm state without manual intervention by maintenance engineers.

If the PBX and IGX configurations are both set to Common Channel Signalling (CCS), this problem may appear when the channels on the PBX interface are manually put out of service, or when one of the channel Permanent Virtual Circuits (PVCs) terminating on the UVM fails.

This problem occurs only when the CCS feature is enabled via the cnflnsigparm command:

12 CVM & UVM Condition T1 Lines? [ YES]

This problem occurs only in 9.2.30 and earlier versions of 9.2. This problem does not occur in any 9.1 or earlier versions of software since the feature was not available in those releases. 9.3 software, currently unreleased and under development, has the fix for this problem.

This problem is caused by software. UVM card replacement will not resolve this problem.

Network users will not be able to establish calls through the affected T1 interfaces because the attached PBXs will busy out the channels on the T1 interfaces detecting yellow alarm.

Network maintenance staff will observe that the T1 line is stuck in yellow alarm. Yellow alarm is also known as Remote Alarm Indication (RAI) and is a standard T1 interface alarm.

Link to site:

http://www.cisco.com/warp/public/770/fn10591.shtml

-- Carl Jenkins (Somewherepress@aol.com), January 24, 2000

Answers

Carl, I don't work for Cisco, but they have been doing a lot of work on voice over IP telecommunications that allows a combination of voice and data signals over the web using Internet Protocol. I suspect this is a fun software glitch that does not have any Y2K implications if that is where you are headed with your question.

The PBX appears to attach to this card via a T1 (24 channel 1.544 mgbps) trunk card. If when both the PBX and this UVM card are set to common channel signalling (CCS) and the PBX it is attached to develops a problem and is manually put out of service, or this voice module card loses a virtual circuit, it goes to yellow and they both lock up. Probably until a tech can clear it--hopefully remotely.

Expect they have a competitor or two (Siemens?) giggling on this one

-- Nancy (wellsnl@hotmail.com), January 24, 2000.


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