Input Errors, CRC errors, interface resets

[WILLIAM STEGMAN]

I've been getting these errors sporadically on my serial interfaces, Wan Interface Cards, of 2 routers that connect a leased point to point connection. One is a 2811 and the other a 1720. I have the linecode and framing set the same on both ends(service-module), b8zs and esf. The clock source is internal on the 2811 and set to line on the 1720. The only other setting I can think of is the clock rate on the interfaces, which I've set the same on each end, 2000000. My provider has tested the line several times, and tells me it's a timing issue on the 2811 router's side. They test fine from the smartjack to the CSU/DSU on the 1720 router, but get errors when testing from the smart jack to the CSU/DSU on the 2811 router. They say the timing is at -250, and should only be +-20. What timing needs configured on my router?

Thank you,

Bill

[pkhatri]

Hi Bill,

Are you using the VWIC-1MFT-E1/VWIC-1MFT-E1 cards ? If so, let me tell you that we have had major issues with these cards. In fact, the symptoms we had match yours. In a lot of cases, we had to replace the customers E1 port with a serial one and then use an x21 to E1 converter.

A long-standing TAC case has not been able to satisfactorily resolve this issue for us.

WE have since started to deploy the second-generation VWIC2-2MFT-T1/E1 which seem to be behaving much better.

Paresh

[WILLIAM STEGMAN]

Hi, it's looks like I'm using a WIC-1DSU-T1-V2, so hopefully the problem you experienced doesn't apply here. I remember trying the V1s I had in my old 2610 router, but needed to upgrade to the V2s when I put the 2811 in about 6 months ago, so they're fairly new. Am I missing any part of the correct configuration? I've tried setting the clock rate to 1000000 on the serial interfaces of both routers, but am not sure if that even applied here. I didn't think that needed to be set if the CSU/DSU is integrated.

Here's the output of the sh service-mod after clearing the interfaces' counters

Module type is T1/fractional

Hardware revision is 0.49, Software revision is 20050527,

Image checksum is 0x3EFB7B, Protocol revision is 0.1

Receiver has no alarms.

Framing is ESF, Line Code is B8ZS, Current clock source is internal,

Fraction has 24 timeslots (64 Kbits/sec each), Net bandwidth is 1536 Kbits/sec.

Last module self-test (done at startup): Passed

Last clearing of alarm counters 01:37:04

loss of signal : 0,

loss of frame : 0,

AIS alarm : 0,

Remote alarm : 0,

Module access errors : 0,

Total Data (last 6 15 minute intervals):

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

Data in current interval (420 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

and a show run interface

interface Serial0/1/0

description Pt-to-Pt Connection to Derry st in Harrisburg Circuit ID:13HCGS507006

ip address 10.0.4.1 255.255.255.252

ip access-group 101 in

ip route-cache flow

service-module t1 clock source internal

end

[pkhatri]

What is the distance between the two devices ? If it's a short-distance cable, you may need to configure the cable length ..

Paresh

[WILLIAM STEGMAN]

which cable? The T1 ethernet cable that runs from the WIC to the smarthjack? It is probably 30-40 meters, so I would use

Hummelstown2811(config-if)#service-mo T1 cable sh 220ft

[pkhatri]

I meant the total distance between the two routers...

[WILLIAM STEGMAN]

that's about a mile...I'm a little confused. My router's WIC T1 cable terminates in a smart jack, which leads to the provider's network and our point to point T1.