Service Manual

trac. Route maps process routes for route redistribution. For example, a route map can be called to lter only specic routes and to
add a metric.
Route maps also have an “implicit deny.” Unlike ACLs and prex lists; however, where the packet or trac is dropped, in route maps,
if a route does not match any of the route map conditions, the route is not redistributed.
Implementation Information
The Dell Networking OS implementation of route maps allows route maps with the no match or no set commands. When there
is no match command, all trac matches the route map and the set command applies.
Flow-Based Monitoring Support for ACLs
Flow-based monitoring is supported on the platform.
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 2 and Layer 3 ingress trac. You can specify trac 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 noties 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 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.
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 conguration to the ACL agent. The interface manager noties 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, trac 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 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 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]
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.
The ACL agent module saves monitoring details in its local database and also in the CAM region to monitor packets that match the
specied criterion. The ACL agent maintains data on the source port, the destination port, and the endpoint to which the packet
must be forwarded when a match occurs with the ACL entry.
Access Control Lists (ACLs)
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