Sounds to me like a framing issue with the Telco. I'll bet the problem
disapears and Bell says they found nothing wrong. (he he)
----- Original Message -----
From: <jlewis@lewis.org>
To: <cisco-nsp@puck.nether.net>
Sent: Wednesday, December 26, 2001 4:19 PM
Subject: Re: Odd T1 problem
> One more thing to add...
>
> If a loopback plug is inserted in the smart jack at either the A or Z end,
> the router at the other end sees the loop and can run patterns (all 0's,
> alternating 0's/1's, all 1's) across the loop. Remove the loopback plug
> and plug the routers back in, and the line proto starts flapping again.
> Trun off keepalives, and the protocol stays up, but neither router sees
> packets sent by the other.
>
> Bell is supposed to be having someone make sure the framing/line coding is
> properly set in the DACS and any other equipment the circuit goes through.
>
> On Wed, 26 Dec 2001 jlewis@lewis.org wrote:
>
> > I've got an odd T1 problem I've been unable to solve remotely. It's a
> > BellSouth point to point T1 between 2 locations in the same city. Cisco
> > 1600 and Digital Link Prelude at the Z end, 2620 with WIC-2T and Larscom
> > Access-T's at the A end. All of a sudden, line protocol (we're using
> > hdlc) is flapping on both sides. i.e.
> >
> > Dec 26 19:13:58: %LINEPROTO-5-UPDOWN: Line protocol on Interface
> > Serial0/3, changed state to down
> > Dec 26 19:14:00: %LINEPROTO-5-UPDOWN: Line protocol on Interface
> > Serial0/3, changed state to up
> > Dec 26 19:14:28: %LINEPROTO-5-UPDOWN: Line protocol on Interface
> > Serial0/3, changed state to down
> > Dec 26 19:14:30: %LINEPROTO-5-UPDOWN: Line protocol on Interface
> > Serial0/3, changed state to up
> >
> > This site is a couple hundred miles away, and though I don't have anyone
> > technical there, there is a person able to move wires around. I had
them
> > move the T1 patch cable to another CSU on another WIC-2T port and it
kept
> > doing this...so that eliminates the CSU and WIC port.
> >
> > I've had bell loop the circuit towards the A side and towards the Z
side,
> > and have been able to run extended pings with various patterns across
each
> > half of the circuit. When they reconnect the A and Z ends in the DACS,
> > line protocol goes back to flapping. Until it failed, this circuit had
> > been in use for quite a while, so I don't suspect CSU config issues.
> >
> > All equipment at each end has been power cycled.
> >
> > I haven't tried having the remote people replace patch cables, but I
> > wouldn't think each half of the circuit would have tested ok if there
was
> > a bad cable.
> >
> > Anyone have any idea what this might be? I really don't want to do it,
> > but I've run out of ideas other than grabbing enough spare gear to
replace
> > everything at each end and driving up there to replace all the gear and
> > wiring.
> >
> >
>
> --
> ----------------------------------------------------------------------
> Jon Lewis *jlewis@lewis.org*| I route
> System Administrator | therefore you are
> Atlantic Net |
> _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________
>
>
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