I was sent out to a site where they've recently noticed that six of their PRI circuits (all in the same group) are showing "FE DSBL" on a few of their channels -- one loop *had* quite a few reporting FE DSBL, but Verizon has cleared most of that circuit while testing. In most of the loops it only effects the first channel. What's really odd is that these channels are working (they have no problems with dropped calls etc.). When I STAT the channels they show IDLE. When I direct access them with a maintenance set, I get dial tone and I can call out. When they're busy, I can TRAD them and get the call record and they show BUSY when STATed. So the problem seems to be a bogus error report. Verizon Core Group also sees an FE DSBL (or equivalent report) from their side, but they also note that the channels are working.
I think the CO switch is a Lucent -- but, so far, no hard confirmation. They've got the D channels set to NI2, but CO_TYPE is set to STD. Our in-house engineer thinks that this should probably be set to ATT instead *if* the CO switch is a Lucent, but he's reluctant to screw around with a switch that is working, especially since it's scheduled to go down in a couple weeks for... some kind of mainenance... I wasn't told why exactly. The PRIs do come through CSUs and this is Rel 4. The switch was installed in November and no one noticed this problem until a couple weeks ago -- but that doesn't necessarily mean the problem didn't exist from the start. The onsite tech just got back from school and was experimenting with some of the STAT commands that he had learned there.
At any rate, has anyone ever heard of this problem? It's the first time I've ever seen something like this. Thanks for any ideas.