Administrator Guide

Version Description
9.5(0.1) Introduced on the Z9500.
9.3(0.0) Added support for logging of ACLs on the S4810, S4820T, and Z9000 platforms.
Usage Information
When the congured maximum threshold is exceeded, generation of logs is stopped. When the interval at which
ACL logs are congured to be recorded expires, the subsequent, fresh interval timer is started and the packet
count for that new interval commences from zero. If ACL logging was stopped previously because the congured
threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the congured threshold is exceeded, it is re-enabled after the logging interval
period elapses. ACL logging is supported for standard and extended IPv4 ACLs, IPv6 ACLs, and MAC ACLs. You
can congure ACL logging only on ACLs that are applied to ingress interfaces; you cannot enable logging for ACLs
that are associated with egress interfaces.
You can activate ow-based monitoring for a monitoring session by entering the ow-based enable command in
the Monitor Session mode. When you enable this capability, trac with particular ows that are traversing through
the ingress and egress interfaces are examined and, appropriate ACLs can be applied in both the ingress and
egress direction. Flow-based monitoring conserves bandwidth by monitoring only specied trac instead all trac
on the interface. This feature is particularly useful when looking for malicious trac. It is available for Layer 2 and
Layer 3 ingress and egress trac. You may specify trac using standard or extended access-lists. This mechanism
copies all incoming or outgoing packets on one port and forwards (mirrors) them to another port. The source port
is the monitored port (MD) and the destination port is the monitoring port (MG).
deny icmp (for Extended IP ACLs)
To drop all or specic internet control message protocol (ICMP) messages, congure a lter.
NOTE
: Only the options that have been newly introduced in Release 9.3(0.0) and Release 9.4(0.0) are described here. For a
complete description on all of the keywords and variables that are available with this command, refer the topic of this command
discussed earlier in this guide.
Syntax
deny icmp {source mask | any | host ip-address} {destination mask | any | host
ip-address} [dscp] [message-type] [count [byte]] [order] [fragments] [log
[interval minutes] [threshold-in-msgs [count]] [monitor]
To remove this lter, you have two choices:
• Use the no seq sequence-number command if you know the lter’s sequence number.
•
Use the no deny icmp {source mask | any | host ip-address} {destination mask |
any | host ip-address} command.
Parameters
log (OPTIONAL) Enter the keyword log to enable the triggering of ACL log messages.
threshold-in msgs
count
(OPTIONAL) Enter the threshold-in-msgs keyword followed by a value to indicate
the maximum number of ACL logs that can be generated, exceeding which the generation
of ACL logs is terminated with the seq, permit, or deny commands. The threshold
range is from 1 to 100.
interval minutes (OPTIONAL) Enter the keyword interval followed by the time period in minutes at
which ACL logs must be generated. The time interval range is from 1 to 10 minutes.
282 Access Control Lists (ACL)