Administrator Guide
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [log [threshold-
in-msgs count] ]
2 Specify the interval in minutes at which ACL logs must be generated. You can enter an interval in the range of 1-10 minutes. The
default frequency at which ACL logs are generated is 5 minutes. If ACL logging is stopped because the congured threshold has
exceeded, it is re-enabled after the logging interval period elapses. ACL logging is supported for standard and extended IPv4 ACLs,
IPv6 ACLs, and standard and extended MAC ACLs. Congure ACL logging only on ACLs that are applied to ingress interfaces; you
cannot enable logging for ACLs that are associated with egress interfaces.
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [log [interval
minutes]]
Flow-Based Monitoring Support for ACLs
Flow-based monitoring conserves bandwidth by monitoring only the specied trac instead of all trac on the interface. It is available for
Layer 2 and Layer 3 ingress trac. You can specify trac using standard or extended access-lists. This mechanism copies incoming
packets that matches the ACL rules applied on the ingress 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).
The port mirroring application maintains and performs all the monitoring operations on the chassis. ACL information is sent to the ACL
manager, which in turn noties the ACL agent to add entries in the CAM area. Duplicate entries in the ACL are not saved.
When a packet arrives at a port that is being monitored, the packet is validated against the congured ACL rules. If the packet matches an
ACL rule, the system examines the corresponding ow processor to perform the action specied for that port. If the mirroring action is set
in the ow processor entry, the destination port details, to which the mirrored information must be sent, are sent to the destination port.
When a stack unit is reset or a stack unit undergoes a failure, the ACL agent registers with the port mirroring application. The port mirroring
utility downloads the monitoring conguration to the ACL agent. The interface manager noties the port mirroring application about the
removal of an interface when an ACL entry associated with that interface to is deleted.
Behavior of Flow-Based Monitoring
Activate ow-based monitoring for a monitoring session by entering the flow-based enable command in the Monitor Session mode.
When you enable this capability, trac with particular ows that are traversing through the ingress interfaces are examined, and
appropriate ACLs can be applied in the ingress direction. By default, ow-based monitoring is not enabled.
You must specify the monitor option with the permit, deny, or seq command for ACLs that are assigned to the source or the
monitored port (MD) to enable the evaluation and replication of trac that is traversing to the destination port. Enter the keyword
monitor with the seq, permit, or deny command for the ACL rules to allow or drop IPv4, IPv6, ARP, UDP, EtherType, ICMP, and TCP
packets. The ACL rule describes the trac that you want to monitor, and the ACL in which you are creating the rule will be applied to the
monitored interface. Flow monitoring is supported for standard and extended IPv4 ACLs, standard and extended IPv6 ACLs, and standard
and extended MAC ACLs.
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [count [byte]]
[order] [fragments] [log [threshold-in-msgs count]] [monitor session-ID]
If the number of monitoring sessions increases, inter-process communication (IPC) bandwidth utilization will be high. The ACL manager
might require a large bandwidth when you assign an ACL, with many entries, to an interface.
Access Control Lists (ACLs)
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