Users Guide

Command History
Version Description
9.8(0.0P5) Introduced on the S4048-ON.
9.8(0.0P2) Introduced on the S3048-ON.
9.7(0.0) Introduced on the S6000–ON.
9.5(0.1) Introduced on the Z9500.
9.4(0.0) Added support for ow-based monitoring on the S4810, S4820T, S6000, Z9000,
and MXL 10/40GbE Switch IO Module platforms.
9.3(0.0) Added support for logging of ACLs on the S4810, S4820T, Z9000, and MXL
10/40GbE Switch IO Module platforms.
Usage Information
When the congured maximum threshold is exceeded, generation of logs is stopped. When the interval at
which ACL logs are congured 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 congured threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the congured 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 congure 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 ow-based monitoring for a monitoring session by entering the ow-based enable
command in the Monitor Session mode. When you enable this capability, trac with particular ows 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
specied trac instead all trac on the interface. This feature is particularly useful when looking for
malicious trac. It is available for Layer 2 and Layer 3 ingress and egress trac. You may specify trac 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).
deny tcp (for IPv6 ACLs)
Congure a lter that drops TCP packets that match the lter criteria.
Syntax
deny tcp {source address mask | any | host ipv6-address} [operator port
[port]] {destination address | any | host ipv6-address} [bit] [operator
port [port]] [count [byte]] [log [interval minutes] [threshold-in-msgs
[count]] [monitor]
To remove this lter, you have two choices:
Use the no seq sequence-number command syntax if you know the lter’s sequence number
Use the no deny tcp {source address mask | any | host ipv6-address}
{destination address | any | host ipv6-address} command
Parameters
log (OPTIONAL) Enter the keyword log to enable the triggering of ACL log messages.
Access Control Lists (ACL)
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