CLI Guide
fragments Enter the keyword fragments to use ACLs to control packet fragments.
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.
monitor (OPTIONAL) Enter the keyword monitor when the rule is describing the trac that you 
want to monitor and the ACL in which you are creating the rule is applied to the 
monitored interface.
Defaults By default, 10 ACL logs are generated if you do not specify the threshold explicitly. The default frequency at which 
ACL logs are generated is ve minutes. By default, ow-based monitoring is not enabled.
Command Modes ACCESS-LIST
Supported Modes Full–Switch
Command History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.4(0.0) Added the support for ow-based monitoring on theMXL 10/40GbE Switch IO Module 
platform.
9.3(0.0) Added the support for logging of ACLs on the MXL 10/40GbE Switch IO Module 
platform.
Usage Information
When the congured maximum threshold is exceeded, generation of logs is stopped. When the interval at which 
ACL logs are congured 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 congured 
threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the congured 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 congure 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 flow-based enable 
command in the Monitor Session mode. When you enable this capability, trac 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 directions. Flow-based monitoring conserves bandwidth by monitoring only specied trac 
instead all trac on the interface. This feature is particularly useful when looking for malicious trac. It is available 
for Layer 2 and Layer 3 ingress and egress trac. You may specify trac 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).
262 Access Control Lists (ACL)










