Users Guide
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.
9.4(0.0) Added support for flow-based monitoring on the S4810, S4820T, S6000, and Z9000 
platforms.
9.5(0.1) Introduced on the Z9500.
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 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).
deny (for IPv6 ACLs)
Configure a filter that drops IPv6 packets that match the filter criteria.
Syntax
deny {ipv6-protocol-number | icmp | ipv6 | tcp | udp} [count [byte]] [dscp 
value] [order] [fragments] [log [interval minutes] [threshold-in-msgs [count]] 
[monitor] [no-drop]
To remove this filter, you have two choices:
• Use the no seq sequence-number command syntax if you know the filter’s sequence number
•
Use the no deny {ipv6-protocol-number | icmp | ipv6 | tcp | udp} 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 terminated. 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 time interval range is from 1 to 10 minutes.
Access Control Lists (ACL) 301










