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irregular line protocol flapping on HSSI

I have been experiencing flapping (only line protocol) on this interface from time to time.

I contacted our upstream we are connected to via this interface but there were not any error indications on his side.

I would like to ask you to provide me with some recommendations in this issue.

Please find a printout og "sh int HSSI" below.

Hssi11/0 is up, line protocol is up

Hardware is cxBus HSSI

MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,

reliability 255/255, txload 17/255, rxload 57/255

Encapsulation FRAME-RELAY IETF, crc 16, loopback not set

Keepalive set (10 sec)

LMI enq sent 710362, LMI stat recvd 705854, LMI upd recvd 0, DTE LMI up

LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0

LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE

Broadcast queue 0/256, broadcasts sent/dropped 0/0, interface broadcasts 0

Last input 00:00:01, output 00:00:00, output hang never

Last clearing of "show interface" counters 11w5d

Queueing strategy: fifo

Output queue 0/40, 807776 drops; input queue 0/75, 5732 drops

30 second input rate 9977000 bits/sec, 1672 packets/sec

30 second output rate 3101000 bits/sec, 1296 packets/sec

1689997250 packets input, 2615467679 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 31 throttles

0 parity

67455362 input errors, 0 CRC, 0 frame, 67455362 overrun,, 0 abort

1851303162 packets output, 661571480 bytes, 0 underruns

0 output errors, 0 applique, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

Please fin


Re: irregular line protocol flapping on HSSI

You have a very large nuber of errors:

"67455362 input errors" approx 1% traffic.



Number of times the serial receiver hardware was unable to hand received data to a hardware buffer because the input rate exceeded the receiver's ability to handle

the data."

With that large number of errors the link

can flap (LMI packets dropped).