Let class begin.
>I have a Laurus LA-103 NI on my wall that belongs to Telco from =
there I
have my
cable to an Adtran TSU-LT from there to my IRX-211
What lights or LED's are on the NIU? What happens when you see =
errors occurring on the NIU?
>The Atran TSU-LT is receiving in the ball park of 15 seconds of =
"code
violations and bpvs" every HOUR. The couter on show S1 is showing =
about
the following every HOUR
Your Adtran is a very important piece of equipment to be used when =
troubleshooting. We have several components here that we need to =
isolate where the trouble is coming from.
First there is the T1 line. The T1 has passed the loop tests, so =
next we need to verify the settings on the CSU. You need to know =
what you ordered from the telco. It will probably be something =
like a full T1, ESF, B8ZS, and you should take your timing from =
the loop. Bi-polar violations are a T1 error. The cable between =
your IRX and the CSU cannot cause Bi-polar errors. This, however, =
does not mean the cable isn't bad necessarily.
You can also verify if your Adtran is running OK by putting a loop =
back towards the CSU and verifying that it can run clean to it's =
own loop. You do have a loop plug don't you? If you don't, get =
one. It will become anothe invaluable tool for you to use.
> Status: ESTABLISHED
Input: 252757035 Abort Errors: 7/4
Output: 98489683 CRC Errors: 168
Pending: 0 Overrun Errors: 0
TX Errors: 0 Frame Errors: 157
The aborts and the CRC's and the frame errors *could* be caused by =
the cable between the CSU and the router, but if the Adtran says =
there's trouble coming into it, I would troubleshoot and fix that =
first.=20
>Uptime 1 hour... I have replaced every cable and tightened down =
every wire
possible. Yet I keep getting errors.=20
How is everything wired up coming in from the telco. You should =
have the NIU, then possibly a jack or a punchdown block, then a =
cable to the CSU. What kind of cable are you using? If it's the =
flat satin stuff, throw it away - immediately!
Clear the counters on the Adtran and clear the performance =
monitoring also. Check it to see what alarms and/or errors are =
accumulating.=20
>The telco says they can loop to the NI and it runs clean. =20
They say they can loop to my csu and run clean.
They have done several 20 minute intrusive tests and they are =
telling me
that it is my router or the cable from my csu to the router that =
is bad. I
have swapped the cable with a know good cable.
Loop tests are not the end all be all of testing. They are a good =
indication, but almost worthless at finding intermittent trouble.=20=
>Is it possible, reasonable that the router is causing these =
errors.???
The router can't CAUSE errors on the T1. You have to keep in mind =
that from the router's perspective, you can only see what is =
coming in from the CSU, and the CSU can only see what is coming in =
from the span. You have no idea what is happening going the other =
direction. Does PacBell see errors on the physical level coming =
into their frame relay switch?
>Any advice ???
Check to see what's happening going the other direction, and you =
could always request a monitor be placed somewhere in the span =
(looking both directions) to help further isolate trouble.
>Thanks
Your welcome, class dismissed.
Kyle Platts
CSS-Tech
!NTERPRISE Networking Services=