moto PCU--cisco router----Z ADM------CPOS----NE40---PDSN
from moto site ,they ping IP address of interface on NE40 from cisco router ,many packets lost , from NE40 ping CISCO ,few packets
Mar 28 19:30:59 2007 NE40 SRM/5/System bucket overflow:OID=22.214.171.124.4.1.2011.2.1
7.0.263. On board 8, bucket 31 discard packet
#Mar 28 19:33:00 2007 NE40 SRM/5/System bucket overflow Resume:OID=126.96.36.199.4.1.2
011.2.17.0.264. On board 8, bucket 31 don't discard packet yet
From logfile , we find only bucket 31overflow, bucket 31 used from ICMP packets.
confirm with moto engineer, capture the packet , no ping attack . except this reaon.
using the command "display system-bucket " to check all the buckets , find the pakcets lost increased on bucket 31 .
The default value is 16k for bucket 31. After we change the deepth of bucket 31 to 64K. ping test checked. no packets lost , the problem is solved.
The possible reason: 1,acl configured. 2,ping attack.
The defaule value of bucket 31 is 16K, the purpose of this to prevent the ping attack. do not modify this vlaue to large.