HP ProCurve 2910al Access Security Manual page 381

ACE Counter Operation: For a given ACE in an assigned
ACL, the counter increments by 1 each time the switch detects
a packet that matches the criteria in that ACE, and maintains
a running total of the matches since the last counter reset.
For example, in ACL line 10 below, there has been a total of 37
matches on the ACE since the last time the ACL's counters were
reset.
Total
( 37) 10 permit icmp 10.10.20.3
Note: This ACL monitoring feature does not include hits on
the "implicit deny" that is included at the end of all ACLs.
Resetting ACE Hit Counters to Zero:
• Removing an ACL from an interface zeros the ACL's ACE
counters for that interface only.
• For a given ACL, either of the following actions clear the ACE
counters to zero for all interfaces to which the ACL is
assigned.
– adding or removing a permit or deny ACE in the ACL
– rebooting the switch
IPv4 Access Control Lists (ACLs)
Monitoring Static ACL Performance
9-93