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Input Errors on MLPPP Interface

We created a two T1 multilink between a Cisco 7500 and 1700 series routers. The 1700 has recent 12.3 code. For some reason, we are getting accumulating input, frame, and overrun errors on the multilink interface on the 1700. The Serial0 and Serial1 interfaces do not show any errors... only on the multilink. Also, "sh service-module" is clean for both interfaces so there does not appear to be a provider or local cabling issue, correct?

Shouldn't we see errors on the physical interfaces as well?

routerB#sh int mu2

Multilink2 is up, line protocol is up

Hardware is multilink group interface

Internet address is <blank>

MTU 1500 bytes, BW 3088 Kbit, DLY 100000 usec,

reliability 255/255, txload 14/255, rxload 30/255

Encapsulation PPP, LCP Open, multilink Open

Open: IPCP, CDPCP, loopback not set

Keepalive set (10 sec)

DTR is pulsed for 2 seconds on reset

Last input 00:00:00, output never, output hang never

Last clearing of "show interface" counters 08:44:14

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 364000 bits/sec, 100 packets/sec

5 minute output rate 175000 bits/sec, 121 packets/sec

779719 packets input, 411628751 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

264 input errors, 0 CRC, 193 frame, 9 overrun, 0 ignored, 0 abort

877089 packets output, 139788365 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

routerB#sh ppp multilink

Multilink2, bundle name is router

Bundle up for 10:39:00, total bandwidth 3088, load 18/255

Receive buffer limit 24384 bytes, frag timeout 1000 ms

0/0 fragments/bytes in reassembly list

98 lost fragments, 185689 reordered

237/225485 discarded fragments/bytes, 237 lost received

0x1157D4 received sequence, 0x103F86 sent sequence

Member links: 2 active, 0 inactive (max not set, min not set)

Se1, since 10:38:57

Se0, since 09:42:11

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Re: Input Errors on MLPPP Interface

Try these (one at a time or all at once):

debug ppp authentication

debug ppp negotiation

debug ppp multilink

debug ppp error

debug ppp packet

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