Avaya Connect Partner Link Image
New Jersey Chamber Of Commerce Member Link Graphic

State of New Jersey
Board of Examiners of Electrical Contractors Telecommunications Limited Wiring Exemption
License Number 1877

Follow Us On Twitter

BCM Digital Station Loop Error

For the past few weeks I've been having issues with a Nortel BCM 400. We've gone from moving modules around back in March when the lines weren't answering to replacing the hard drive and restoring. All seemed ok after that. This past Monday our client called stating that about half of their phones were randomly rebooting. This was a new issue and by the time I got there everything was fine. I asked the IT manager for a list of the extensions rebooting, but he had none. All I had to go on was the error in the Alarm Log stating, “Critical error 247 - Core Telephony - Digital Station Loop Error." Of course the error has the little note stating to check that the phones are plugged in etc. Just the basic stuff to check. None of it applied to my situation. Tried to Google it and only found about three mentions on TekTips.com I think. All stated the same thing as a solution which was to check the Dip Switch settings on the DSM 16+ module. This wasn't my problem as the settings didn't magically change over the weekend. So I hung around and waited for the issue to happen again. Of course it didn't. I left after about 3 hours. Our client called again today (Thursday) stating that the phones were once again rebooting at random. I quickly ran over and was able to see it happening for myself. The IT manager was off so I asked the very helpful receptionist to send out an email requesting anyone with this problem to reply. She was able to get me a list of about 15 extensions which I was able to break down to ports and in turn modules. Turned out that it was both DSM 16+ modules this was happening to. I figured the chance of two modules going bad at the exact same time was very unlikely. I logged in and there were about 100 errors in the Alarm log. All the same, "digital station loop error." The phones had since stopped rebooting and working normally. About an hour and a half later it happened again multiple times. This time I was standing next to the BCM and saw that the lights on both of the DSM 16+ modules were going red and then green and back to red until the phone rebooting stopped. Both modules were on the same back plane! Long story short, the client had their old BCM 400 chassis that we replaced last year. It actually had a faulty back plane in it too, but half was still good. I was able to break off the good section and replace the bad section of the existing unit. All booted up good and was working like a champ. I'm 99% sure that the back plane was the problem. If not I'll update this page later.

Updated 5/4/10

Our client called again this morning stating that the phones were once again rebooting at random. Damn, I was so sure it was the backplane. At first I was going to replace one of the DSM 16+ modules with a new one I had picked up on the way over, but I had another idea. After checking the alarm logs I shut the BCM down and swapped the trunk modules from the good backplane to where my two DSM 16+ modules were etc. After boot up all seemed to be functioning normally. The Nortel tech at our distributor had been stating that the problem could be a patch that hasn't been applied. So off I went on a futile attempt to find any patches on Nortel's website. Didn't find any patches at all. They must hide them really good. While there I decided to check the knowledgebase once again. This time I typed in the alarm id 247 and found the answer. Back in 2005 Nortel made some BCM's with faulty power connectors. After a while the pins no longer make a good contact with the backplane causing intermittent resets of whatever module happens to be there. I was able to verify my BCM product code was one of the effected models. I also manually made the cards reset by moving the wires attached to the connector. After replacing the bad connector all was once again right in the world. Hope this helps someone out there.

Updated 05/14/10

Happy to report that our customer has had smooth sailing so far. No more issues.

Mastercable NY - NJ Service Area

We will be happy to meet with you to discuss your Voice, Data, Audio / Video cabling, Home Theater or IT needs. We will consult, design and build in the following counties...

New Jersey

Bergen, Essex, Hudson, Middlesex, Morris, Passaic, Somerset and Union.

New York

Bronx, Kings, Nassau, New York, Queens, Putnam, Richmond, Rockland and Westchester



Call Now To Schedule A Free Site Survey!

877-240-5472 or 973-547-2669

or Email Us