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Version Description
9.4(0.0) Added support for flow-based monitoring on the S4810,
S4820T, S6000, and Z9000 platforms.
9.3(0.0) Added support for logging of ACLs on the S4810, S4820T,
and Z9000 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 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
theflow-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 — Assigns a IP ACL filter to deny IP packets.
ip access-list standard — Creates a standard ACL.
permit arp (for Extended MAC ACLs)
Configure a filter that forwards ARP packets meeting this criteria. This command is supported only on 12-
port GE line cards with SFP optics; refer to your line card documentation for specifications.
Syntax
permit arp {destination-mac-address mac-address-mask | any}
vlan vlan-id {ip-address | any | opcode code-number} [count
[byte]] [order] [fragments] [log [interval minutes] [threshold-
in-msgs [count]][monitor]
To remove this filter, you have two choices:
Access Control Lists (ACL)
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