Service Manual

If ACL logging is stopped because the configured 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 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 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).
Related
Commands
• deny — configure a filter to drop packets.
• permit — configure a filter to forward packets.
seq (for IPv6 ACLs)
Assign a sequence number to a deny or permit the filter in an IPv6 access list while creating the filter.
Syntax
seq sequence-number {deny | permit} {ipv6-protocol-number | icmp |
ip | tcp | udp} {source address mask | any | host ipv6-address}
{destination address | any | host ipv6-address} [operator port
[port]] [count [byte]] [log [interval minutes] [threshold-in-msgs
[count]] [monitor]
To delete a filter, use the no seq sequence-number 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 terminate 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.
Access Control Lists (ACL) 385