Administrator Guide

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. You can enter a threshold in the range of 1-100.
interval
minutes
(OPTIONAL) Enter the keyword interval followed by the
time period in minutes at which ACL logs must be generated.
You can enter an interval in the range of 1-10 minutes.
monitor (OPTIONAL) Enter the keyword monitor when the rule is
describing the traffic 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 5 minutes. By default,
flow-based monitoring is not enabled.
Command
Modes
CONFIGURATION-EXTENDED-ACCESS-LIST
Command
History
Version 9.3.0.0 Added support for logging of ACLs on the S4810, S4820T,
Z9000, and MXL 10/40GbE Switch IO Module platforms.
Version 9.4(0.0) Added support for flow-based monitoring on the S4810,
S4820T, S6000, Z9000, and MXL 10/40GbE Switch IO
Module platforms.
Usage
Information
When the configured maximum threshold is exceeded, generation of logs is
stopped. When the interval at which ACL logs are configured 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 configured threshold is exceeded, it is reenabled for this new interval.
If ACL logging is stopped because the configured threshold is exceeded, it is
reenabled after the logging interval period elapses. ACL logging is supported for
standard and extended IPv4 ACLs, standard and extended IPv6 ACLs, and standard
and extended MAC ACLs. You can configure 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 flow-based monitoring for a monitoring session by entering the
flow-based enable command in the Monitor Session mode. When you enable this
capability, traffic with particular flows 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 specified traffic instead all traffic on the interface. This feature is
particularly useful when looking for malicious traffic. It is available for Layer 2 and
Access Control Lists (ACL)
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