Users Guide

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 re-enabled for this new interval.
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
• ip access-list extended — create an extended ACL.
• permit — assign a permit filter for IP packets.
• permit udp — assign a permit filter for UDP packets.
seq arp (for Extended MAC ACLs)
Configure an egress filter with a sequence number that filters ARP packets meeting this criteria. This
command is supported only on 12-port GE line cards with SFP optics. For specifications, refer to your line
card documentation.
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
seq sequence-number {deny | permit} arp {destination-mac-address
mac-address-mask | any} vlan vlan-id {ip-address | any | opcode
code-number} [count [byte]] [order] [log [interval minutes]
[threshold-in-msgs [count]] [monitor]
To remove this filter, use the no seq sequence-number command.
Parameters
log (OPTIONAL) Enter the keyword log to enable the triggering of
ACL log messages.
Access Control Lists (ACL) 380