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
Layer 3 ingress and egress traffic. You may specify traffic 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).
seq (for IP ACLs)
Assign a sequence number to a deny or permit filter in an extended IP access list while creating the filter.
Syntax seq sequence-number {deny | permit} {ip-protocol-number | icmp
| ip | tcp | udp} {source mask | any | host ip-address}
{destination mask | any | host ip-address} [operator port
[port]] [count [byte]] [dscp value] [order] [fragments] [log
[interval minutes] [threshold-in-msgs [count]] [monitor]
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 interval range is from 1 to 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 five minutes. By default,
flow-based monitoring is not enabled.
Command
Modes
CONFIGURATION-EXTENDED-ACCESS-LIST
356 Access Control Lists (ACL)