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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 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 — configure a filter to drop packets.
● permit — configure a filter to forward packets.
seq (for IPv6 ACLs)
Assign a sequence number to a deny or permit the filter in an IPv6 access list while creating the filter.
Syntax
seq sequence-number {deny | permit} {ipv6-protocol-number | icmp | ip | tcp
| udp} {source address mask | any | host ipv6-address} {destination address
| any | host ipv6-address} [operator port [portnumber | portname]] [count
[byte]] [log [interval minutes] [threshold-in-msgs [count]] [monitor]
To delete a filter, use the no seq sequence-number command.
Parameters
sequence-
number
Enter a number from 0 to 4294967290.
deny Enter the keyword deny to configure a filter to drop packets meeting this
condition.
permit Enter the keyword permit to configure a filter to forward packets meeting this
criteria.
ipv6-protocol-
number
Enter a number to filter based on the protocol identified in the IPv6 protocol
header.
icmp Enter the keyword icmp to configure an ICMP access list filter.
ip Enter the keyword ip to configure a generic IP access list. The keyword ip
specifies that the access list permits all IP protocols.
tcp Enter the keyword tcp to configure a TCP access list filter.
udp Enter the keyword udp to configure a UDP access list filter.
source Enter an IP address in dotted decimal format of the network from which the packet
was received.
mask (OPTIONAL) Enter a network mask in /prefix format (/x) .
Access Control Lists (ACL) 287