Users Guide

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 buered in queue 7, though you intended
for these packets to match positive against cmap2 and be buered in queue 4.
In cases where class-maps with overlapping ACL rules are applied to dierent 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 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
Dell(conf)#ip access-list standard acl1
Dell(config-std-nacl)#permit 20.0.0.0/8
Dell(config-std-nacl)#exit
Dell(conf)#ip access-list standard acl2
Dell(config-std-nacl)#permit 20.1.1.0/24 order 0
Dell(config-std-nacl)#exit
Dell(conf)#class-map match-all cmap1
Dell(conf-class-map)#match ip access-group acl1
Dell(conf-class-map)#exit
Dell(conf)#class-map match-all cmap2
Dell(conf-class-map)#match ip access-group acl2
Dell(conf-class-map)#exit
Dell(conf)#policy-map-input pmap
Dell(conf-policy-map-in)#service-queue 7 class-map cmap1
Dell(conf-policy-map-in)#service-queue 4 class-map cmap2
Dell(conf-policy-map-in)#exit
Dell(conf)#interface te 10/1
Dell(conf-if-te-10/1)#service-policy input pmap
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
dierent), matching a packet against these clauses is a logical OR operation.
– Two or more match clauses within the same route-map sequence have dierent 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 specied route-map sequence is processed after a
match is found.
Conguration Task List for Route Maps
Congure 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 conguration tasks for route maps, as described in the following sections.
• Create a route map (mandatory)
• Congure route map lters (optional)
• Congure a route map for route redistribution (optional)
• Congure a route map for route tagging (optional)
Creating a Route Map
Route maps, ACLs, and prex lists are similar in composition because all three contain lters, but route map lters do not contain the
permit and deny actions found in ACLs and prex lists.
Route map lters match certain routes and set or specic values.
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Access Control Lists (ACLs)