Install Guide

Determine the Order in which ACLs are Used to Classify Traffic
When you link class-maps to queues using the service-queue command, Dell EMC Networking OS matches the class-maps
according to queue priority (queue numbers closer to 0 have lower priorities).
As shown in the following example, class-map cmap2 is matched against ingress packets before cmap1.
ACLs acl1 and acl2 have overlapping rules because the address range 20.1.1.0/24 is within 20.0.0.0/8. Therefore (without the
keyword order), packets within the range 20.1.1.0/24 match positive against cmap1 and are buffered in queue 7, though you
intended for these packets to match positive against cmap2 and be buffered in queue 4.
In cases where class-maps with overlapping ACL rules are applied to different queues, use the order keyword to specify the
order in which you want to apply ACL rules. The order can range from 0 to 254. Dell EMC Networking OS writes to the CAM
ACL rules with lower-order numbers (order numbers closer to 0) before rules with higher-order numbers so that packets are
matched as you intended. By default, all ACL rules have an order of 255.
Example of the order Keyword to Determine ACL Sequence
Important Points to Remember
● For route-maps with more than one match clause:
○ Two or more match clauses within the same route-map sequence have the same match commands (though the values
are different), matching a packet against these clauses is a logical OR operation.
○ Two or more match clauses within the same route-map sequence have different match commands, matching a packet
against these clauses is a logical AND operation.
● If no match is found in a route-map sequence, the process moves to the next route-map sequence until a match is found, or
there are no more sequences.
● When a match is found, the packet is forwarded and no more route-map sequences are processed.
○ If a continue clause is included in the route-map sequence, the next or a specified route-map sequence is processed after
a match is found.
Configuration Task List for Route Maps
Configure route maps in ROUTE-MAP mode and apply the maps in various commands in ROUTER RIP and ROUTER OSPF
modes.
The following list includes the configuration tasks for route maps, as described in the following sections.
● Create a route map (mandatory)
● Configure route map filters (optional)
● Configure a route map for route redistribution (optional)
● Configure a route map for route tagging (optional)
Creating a Route Map
Route maps, ACLs, and prefix lists are similar in composition because all three contain filters, but route map filters do not
contain the permit and deny actions found in ACLs and prefix lists.
Route map filters match certain routes and set or specific values.
To create a route map, use the following command.
● Create a route map and assign it a unique name. The optional permit and deny keywords are the actions of the route map.
CONFIGURATION mode
route-map map-name [permit | deny] [sequence-number]
The default is permit.
The optional seq keyword allows you to assign a sequence number to the route map instance.
The default action is permit and the default sequence number starts at 10. When you use the keyword deny in configuring a
route map, routes that meet the match filters are not redistributed.
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Access Control Lists (ACLs)