Concept Guide

IPv6 ACLs, and standard and extended MAC ACLs. 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.
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [log [interval
minutes]]
Flow-Based Monitoring
Flow-based monitoring conserves bandwidth by monitoring only the specied trac instead of all trac on the interface. It is available for
Layer 3 ingress and known unicast egress trac. You can specify the trac that needs to be monitored using standard or extended
access-lists. The ow-based monitoring mechanism copies packets that matches the ACL rules applied on the 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).
When a packet arrives at a port that is being monitored, the packet is validated against the congured ACL rules. If the packet matches an
ACL rule, the system examines the corresponding ow processor to perform the action specied 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.
Behavior of Flow-Based Monitoring
You can activate ow-based monitoring for a monitoring session using the flow-based enable command in the Monitor Session mode.
When you enable this ow-based monitoring, trac with particular ows that are traversing through the interfaces are examined in
accordance with the applied ACLs. By default, ow-based monitoring is not enabled.
There are two ways in which you can enable ow-based monitoring in Dell EMC Networking OS. You can create an ACL and apply that ACL
either to an interface that needs to be monitored or apply it in the monitor session context. If you apply the monitor ACL to an interface,
the Dell EMC Networking OS mirrors the ingress trac with an implicit deny applied at the end of the ACL. If you apply the ACL to the
monitor section context, the Dell EMC Networking OS mirrors the ingress and known unicast egress trac with an implicit permit applied
at the end of the ACL. This enables the other trac to ow without being blocked by the ACL.
When you apply an ACL within the monitor session, it is applied to all source interfaces congured in the monitor session.
The Dell EMC Networking OS honors any permit or deny actions of the ACL rules used for ow-based mirroring. Packets that match a
mirror ACL rule is denied or forwarded depending on the rule but the packet is mirrored. However, the user ACL has precedence over the
mirror ACL.
The same source interface can be part of multiple monitor sessions.
Flow-based monitoring is supported for SPAN, RSPAN, and ERSPAN sessions. If there are overlapping rules between ACLs applied on
dierent monitor sessions, the session with the highest monitor session ID takes precedence.
NOTE
: You can apply only IPv4 ACL rules under monitor session context.
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 trac 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 trac that you want to monitor, and the ACL in which you are creating the rule is 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]
Access Control Lists (ACLs)
137