CLI Guide

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 — configures a MAC ACL filter to drop packets.
seq —configure a MAC ACL filter with a specified sequence number.
permit ether-type (for Extended MAC ACLs)
Configure a filter that allows traffic with specified types of Ethernet packets. This command is supported
only on 12-port GE line cards with SFP optics. For specifications, refer to your line card documentation.
Syntax
permit ether-type protocol-type-number {destination-mac-address
mac-address-mask | any} vlan vlan-id {source-mac-address mac-
address-mask | any} [count [byte]] [order] [log
[intervalminutes][threshold-in-msgs] [count]][monitor]
To remove this filter, you have two choices:
• Use the no seq sequence-number command if you know the filter’s
sequence number.
• Use the no permit ether-type protocol-type-number
{destination-mac-address mac-address-mask | any} vlan vlan-
id {source-mac-address mac-address-mask | any} command.
Parameters
protocol-type-
number
Enter a number from 600 to FFF as the specific Ethernet
type traffic to drop.
destination-mac-
address mac-
address-mask
Enter a MAC address and mask in the nn:nn:nn:nn:nn
format.
For the MAC address mask, specify which bits in the MAC
address must match.
The MAC ACL supports an inverse mask; therefore, a mask
of ff:ff:ff:ff:ff:ff allows entries that do not match and a mask
of 00:00:00:00:00:00 only allows entries that match
exactly.
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Access Control Lists (ACL)