Loopback commands for testing

[rgonzaga]

I'm in the process of trying to troubleshoot the massive errors I'm receiving on one end of 3 T1s. After verifying line codes, framing and clocking with AT&T, I want to test the line with them. The problem is that they've never been able to see my equipment when they loop me. Is there a loopback command that I need to turn on to allow this? I need to turn it on for a VWIC-2MFT-T1 and WIC1-DSU. Thanks.

[thisisshanky]

This link might help!

http://www.cisco.com/warp/public/125/11.html

[rgonzaga]

I've read this page but I'm still not completeley clear:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fdial_c/fnsprt4/dcdchant.htm#1002839

My question is it "loopback local" that needs to be used to allow my service provider to test up to the router. If it is, is the router usable in this mode? I realize intrusive testing brings the line down but once they're done the line comes back up. If the line is in this mode, will this T1 have to wait for me to do a "no loopback local" to bring it up? Thanx.

[deilert]

you may want to turn on service-module t1 fdl both on the serial interface . This allows the Lec to loop the card

[daniel.castro]

It sounds liek you have a Layer 1 issue. Do you have an extended DEMARC? Can ATT loop the SmartJack? If so, place a HARD loop at the end of your extended DEMARC (buy or make one). Once you have the hard loop at teh far end of the extension, have ATT test the circuit again. If they can see the loop, and your are certain your CSU is good, ask ATT to conduct a "STRESS TEST" for your T1 and request it for at least 60 minutes. Remember this is an intrussive test.

[rgonzaga]

Ok, I got AT&T to loop me up and when they did, I saw no errors:

Data in Interval 1:

0 Line Code Violations, 0 Path Code Violations

0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins

0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

As soon as he let go of the line, the errors came back. I 'm not sure what this means. the other end of the T1 shows no errors either. Just the Calif location:

Data in current interval (755 seconds elapsed):

7287 Line Code Violations, 15185 Path Code Violations

221 Slip Secs, 0 Fr Loss Secs, 221 Line Err Secs, 2 Degraded Mins

143 Errored Secs, 143 Bursty Err Secs, 78 Severely Err Secs, 0 Unavail Secs

[vmiller]

how far in did the loop go ? If they went to their dmarc, then you may have cable issues between the demarc and your hardware

[toerierz]

Have you check your framing & clocking ?

Have a look at these links:

http://www.cisco.com/en/US/tech/tk713/tk584/technologies_tech_note09186a00800a5cdc.shtml (Instead of 'e1' use 't1'

http://www.cisco.com/en/US/tech/tk713/tk584/technologies_tech_note09186a00801095a3.shtml

http://www.cisco.com/en/US/tech/tk713/tk584/tk628/tech_protocol_home.html

[deilert]

slips & aborts are usually clocking issues , check with the service provider to find out who provides clock, if the provide clock make sure your service module is set to rx clock from the line . If they do not provide clock (this is generally the case in a point to point ) one side of your circuit needs to be set for internal clock and the other side needs to be set for line .

[rgonzaga]

Agreed. The Vegas side is set to internal while the Los Angeles is set to line. When AT&T looped me up, there were no errors but when they let it go they came back. Almost seems that I'm not able to clock off of Vegas...

[deilert]

try reversing it , have LA provide clock and have Vegas rx

you may also want to try resetting your service module 'clear service-module'

[rgonzaga]

I asked AT&T to run tests again. Their quick Monitor test showed the following errors in their log:

Circuit: A-End: NORGCA11

Test Monitor: 60 Seconds

CSU or Access or AT&T IOC problems between Customer and AT&T.

BEFORE: ES=00000 SES=------ BS=------ UAS=00000 LOFC=------

AFTER: ES=-0802 SES=------ BS=------ UAS=00021 LOFC=------

DS1 Test : Problem detected. Requires further analysis.

So then it gets escalated to an actual tech and he finds nothing wrong:

Intrusive testing not authorized...non-intrusively tested

and checked all access points...clean...no errors...the

csu spoke to me - clean...return to customer for closure.

He didn't read the notes to do intrusive testing at night but still he didn't find anything. If he tested to me with no problems doesn't that just clear me and up to where he tested? What about before that point? What about the errors the quick monitoring found? Any suggestions where to go from here would help a lot.

[deilert]

Ok

This is what you need to do with ATT

first of all if you have an internal CSU make sure you have the command " service-module FDL T1 both ' This will allow for ATT to loop the CSU.

Next when ATT tests find out where they are testing from , they have a bad habit of testing from the closest test point. If they are testing good from there have them test from the same place in the other direction .

Next If they can looping the smart jack have them loop the CSU.

What is showing when you do a ' sh service-module serial x/xperformance-statistics '

Please paste this in from both ends

[rgonzaga]

I have to use the controller t1 commands but assuming you want a "sh controller t1 x/x" . Was there a different command you were looking for. Yes, I do have the FDL both turned on and they were looping me up to the CSU. This is what I got:

Applique type is Channelized T1

Cablelength is short 133

Description: T1 to Las Vegas

Receiver has no alarms.

alarm-trigger is not set

Version info Firmware: 20000922, FPGA: 15

Framing is ESF, FDL is ansi & att, Line Code is B8ZS, Clock Source is Line.

Current port master clock: recovered from controller 3/1

Data in current interval (860 seconds elapsed):

0 Line Code Violations, 0 Path Code Violations

0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins

0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

Notice, no errors.

I will have them loop as you suggested. Looping both side from the same point. I've contested the ticket with AT&T and waiting for a tech to pick it up. Any gut feeling on this yet? Thanks again, man.

[deilert]

What is the sh controllers t1 x/x show on the other end ?

Also You can do a sh controllers t1 x/x this will show you stats over the last 24 hrs