Mailing List Archive

PRI Problem
We have a PRI for ISDN calls and we have been having some problems with
certain users for the last 24 hours. Some users can call in and connect and
no matter what channel they are on, they work fine (they can drop the call
and call back and it works fine). Some users call in and have tons of
dropped packets (if they drop and call back, they still have problems).
There have been no IOS or config changes for at least a week. The PRI
itself is clean, but the individual channels show errors. Any idea what
could cause this? If it was 1 user, I would blame them, but there are 3-4
that just started having this problem recently and there are 3-4 that work
fine. The PRI is clean, so I can't imagine where the errors are
originating. Maybe at the calling CO? Here is some debug info:

T1 0/1 is up. (PRI is clean)
Applique type is Channelized T1
Cablelength is long gain36 0db
Description: XSpedius #1IBRYBRY0361 (800)9espire
No alarms detected.
alarm-trigger is not set
Framing is ESF, Line Code is B8ZS, Clock Source is Line.
Data in current interval (474 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
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
Data in Interval 2:
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 Interval 3:
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


Virtual-Access4, bundle name is xxxxxx (This user has trouble)
Bundle up for 10:05:19
Dialer interface is Serial0/1:23
9673 lost fragments, 15713 reordered, 2 unassigned
31 discarded, 0 lost received, 1/255 load
0xA354 received sequence, 0xA498 sent sequence
Member links: 2 (max not set, min not set)
Se0/1:8, since 10:05:19, last rcvd seq 00A353
Se0/1:9, since 10:05:16, last rcvd seq 00A356

GW1#sh int s 0/1:8
Serial0/1:8 is up, line protocol is up
Hardware is DSX1
MTU 1500 bytes, BW 64 Kbit, DLY 20000 usec,
reliability 157/255, txload 1/255, rxload 1/255
Encapsulation PPP, loopback not set
Keepalive not set
LCP Open, multilink Open
Last input 00:00:02, output 00:00:00, output hang never
Last clearing of "show interface" counters 10:27:22
Input queue: 0/75/12517/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair [suspended, using FIFO]
FIFO output queue 0/40, 0 drops
5 minute input rate 0 bits/sec, 1 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
14429 packets input, 1016185 bytes, 0 no buffer
Received 0 broadcasts, 3169 runts, 0 giants, 0 throttles
12517 input errors, 9617 CRC, 2900 frame, 0 overrun, 0 ignored, 61
abort
21311 packets output, 1509725 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
1 carrier transitions
Timeslot(s) Used:9, Transmitter delay is 0 flags


Virtual-Access6, bundle name is yyyyyyy (This user is fine)
Bundle up for 10:16:01
Dialer interface is Serial0/1:23
0 lost fragments, 7 reordered, 0 unassigned
0 discarded, 0 lost received, 1/255 load
0xD63F received sequence, 0x1E319 sent sequence
Member links: 2 (max not set, min not set)
Se0/1:6, since 10:16:01, last rcvd seq 00D63E
Se0/1:7, since 10:15:59, last rcvd seq 00D63D

GW1#sh int s 0/1:6
Serial0/1:6 is up, line protocol is up
Hardware is DSX1
MTU 1500 bytes, BW 64 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation PPP, loopback not set
Keepalive not set
LCP Open, multilink Open
Last input 00:16:15, output 00:00:02, output hang never
Last clearing of "show interface" counters 10:27:48
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair [suspended, using FIFO]
FIFO output queue 0/40, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
29754 packets input, 1540137 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
64197 packets output, 33275654 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
1 carrier transitions
Timeslot(s) Used:7, Transmitter delay is 0 flags
Re: PRI Problem [ In reply to ]
> quick glans and my gut tells me one of three problems here (not in any
> specific order)
>
> - telco

PRI tests clean and the customers BRI tests clean.


> - cpe even the customer line itself (always the same users having the
> problem?)

Yes. The user can dial in 5 times and hit 5 different channels and they
still have the problem. Other users can dial in 5 times, hit 5 different
channels and they work fine.


> - it could be the modems that they connect too on yourside.

Nope, they hit different channels. Also, it's ISDN to a PRI card, we don't
have modems.

I can't figure it out, it's customer specific to several customers and it
just started in the last 24 hours. Other customers work fine.