[j-nsp] Strange Packet Loss Problem

[Christian Koch]

Hi All,

I am experiencing a strange issue between 2 m40 core routers connect
through an oc48 link

I experience packet loss only when sending packets between 293 and 599
bytes.

I am also speaking to cold telecom about the issue to see if it's a
problem with the sonet link, but as of now the link is not taking any
errors or alarms.

Anyone seen anything strange like this before?

ckoch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 300    
PING 212.71.229.25 (212.71.229.25): 300 data bytes
!.!!.!!.!!!!.!.!....!!.!!!!!..!..!!.!!!..!!.!!....!!.!...!!!...!.!.!..!.
.!!...!....!..!.!.!!.!!.!!....!.!!!!!!..!..!.!!.!..!!.!!^C
--- 212.71.229.25 ping statistics ---
129 packets transmitted, 66 packets received, 48% packet loss
round-trip min/avg/max/stddev = 1.023/1.640/34.095/4.035 ms

ckoch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 400    
PING 212.71.229.25 (212.71.229.25): 400 data bytes
!!!!!!!!.!!!!!...!!^C
--- 212.71.229.25 ping statistics ---
20 packets transmitted, 15 packets received, 25% packet loss
round-trip min/avg/max/stddev = 1.074/1.111/1.348/0.071 ms

ckoch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 500    
PING 212.71.229.25 (212.71.229.25): 500 data bytes
!!!!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.!^C
--- 212.71.229.25 ping statistics ---
49 packets transmitted, 46 packets received, 6% packet loss
round-trip min/avg/max/stddev = 1.141/1.202/2.514/0.210 ms

ckoch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 600    
PING 212.71.229.25 (212.71.229.25): 600 data bytes
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!^C
--- 212.71.229.25 ping statistics ---
955 packets transmitted, 954 packets received, 0% packet loss
round-trip min/avg/max/stddev = 1.183/1.526/36.436/1.817 ms

koch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 292    
PING 212.71.229.25 (212.71.229.25): 292 data bytes
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!^C!
--- 212.71.229.25 ping statistics ---
916 packets transmitted, 916 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.988/1.146/9.918/1.061 ms

ckoch at core2.lhr3> ping rapid 212.71.229.25 count 10000 size 293    
PING 212.71.229.25 (212.71.229.25): 293 data bytes
..!!!.!^C

Christian