PRI will not stay up

[Anonymous]

New AT&T IP flex PRI handoff to Adtran TA 908e 3rd GEN will not stay up. D channel is flapping and B channels go OOS and then back in.

It's a partial PRI 10 B channels and D channel 24. I've reviewed configs with AT&T and we're both setup for NI2. Carrier reports a huge count of Code Violation errors on T1 cross over cable. We've swapped the cable and it remains in trouble.

I've tried LBO commands -7.5, -15 and -22.5 but none seem to make a difference.

Any ideas? I see this in the logs

2020.02.06 15:04:47 ISDN.EP

PRI  2  Call clearing: TIMER_EXPIRY : Loc=U

2020.02.06 15:04:47 ISDN.EP

PRI  2  D channel is DOWN

2020.02.06 15:04:47 TM.T01 0 Taking 10 b-channels out-of-service

2020.02.06 15:04:47 TM.T01 01 tachgClearing processed by IsdnTmState base

2020.02.06 15:04:48 INTERFACE_STATUS.pri 2 changed state to down

2020.02.06 15:04:48 ISDN.EP

PRI  2  D channel is UP

2020.02.06 15:04:49 INTERFACE_STATUS.pri 2 changed state to up

2020.02.06 15:04:50 TM.T01 0 Adding 10 b-channels in-service

2020.02.06 15:05:27 ISDN.EP

PRI  2  D channel is DOWN

2020.02.06 15:05:27 TM.T01 0 Taking 10 b-channels out-of-service

2020.02.06 15:05:27 INTERFACE_STATUS.pri 2 changed state to down

2020.02.06 15:05:27 ISDN.EP

PRI  2  D channel is UP

2020.02.06 15:05:28 INTERFACE_STATUS.pri 2 changed state to up

2020.02.06 15:05:29 TM.T01 0 Adding 10 b-channels in-service

2020.02.06 15:06:06 ISDN.EP

PRI  2  D channel is DOWN

2020.02.06 15:06:06 TM.T01 0 Taking 10 b-channels out-of-service

2020.02.06 15:06:06 INTERFACE_STATUS.pri 2 changed state to down

2020.02.06 15:06:06 ISDN.EP

PRI  2  D channel is UP

2020.02.06 15:06:07 INTERFACE_STATUS.pri 2 changed state to up

2020.02.06 15:06:07 TM.T01 0 Adding 10 b-channels in-service

2020.02.06 15:07:33 ISDN.EP

PRI  2  D channel is DOWN

2020.02.06 15:07:33 TM.T01 0 Taking 10 b-channels out-of-service

2020.02.06 15:07:33 ISDN.EP

PRI  2  D channel is UP

2020.02.06 15:07:34 TM.T01 0 Adding 10 b-channels in-service

2020.02.06 15:09:00 ISDN.EP

PRI  2  D channel is DOWN

2020.02.06 15:09:00 TM.T01 0 Taking 10 b-channels out-of-service

2020.02.06 15:09:00 INTERFACE_STATUS.pri 2 changed state to down

2020.02.06 15:09:01 ISDN.EP

PRI  2  D channel is UP

2020.02.06 15:09:01 INTERFACE_STATUS.pri 2 changed state to up

2020.02.06 15:09:03 TM.T01 0 Adding 10 b-channels in-service

[jayh · Accepted solution]

Sounds like a T1 coding/framing issue. Make sure that your T1 TDM-group configurations have "speed 64" after the timeslots.

"Show Interfaces" will tell you if the Adtran is configured for ESF/B8ZS. It should be.

Also make sure that the TA908e is set to take clocking from the carrier. "Show system" should have the carrier's T1 as the active and primary configured timing source. It's configured with the "timing-source" command.

Check to be sure framing is ESF and linecode is B8ZS throughout the T1 configuration. Look at the smartjack (which is probably made by Adtran). There are indicator lights that are different colors for B8ZS vs. AMI. It should be optioned B8ZS. If not, ask the carrier to fix it.

Can the carrier run clean to the smartjack?