Administrator Guide

To configure IP VLAN and DSCP match criteria in a Layer 3 class map, and apply the class and policy maps to a service queue:
1. Create a match-any or a match-all Layer 3 class map, depending on whether you want the packets to meet all or any of the
match criteria. By default, a Layer 3 class map is created if you do not enter the layer2 option with the class-map
command. When you create a class map, you enter the class-map configuration mode.
CONFIGURATION mode
Dell(conf)#class-map match-all pp_classmap
2. Configure a DSCP value as a match criterion.
CLASS-MAP mode
Dell(conf-class-map)#match ipdscp 5
3. Configure an IP VLAN ID as a match criterion.
CLASS-MAP mode
Dell(conf-class-map)#match ip vlan 5
4. Create a QoS input policy.
CONFIGURATION mode
Dell(conf)#qos-policy-input pp_qospolicy
5. Configure the DSCP value to be set on matched packets.
QOS-POLICY-IN mode
Dell(conf-qos-policy-in)#set ip-dscp 5
6. Create an input policy map.
CONFIGURATION mode
Dell(conf)#policy-map-input pp_policmap
7. Create a service queue to associate the class map and QoS policy map.
POLICY-MAP mode
Dell(conf-policy-map-in)#service-queue 0 class-map pp_classmap qos-policy pp_qospolicy
Ordering ACL Rules
When you link class-maps to queues using the service-queue command, the system matches the class-maps according to
queue priority (queue numbers closer to 0 have lower priorities).
For example, as described in the previous 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, although you
intended for these packets to match positive against cmap2 and be buffered in queue 4.
When class-maps with overlapping ACL rules are applied to different queues, use the keyword order to process ACL rules in
the desired order. ACL rules with lower order numbers (order numbers closer to 0) are applied before rules with higher order
numbers so that packets are matched as you intended.
● Specify the order in which you want to apply ACL rules using the keyword order.
order
The order can range from 0 to 254.
By default, all ACL rules have an order of 254.
Displaying Configured Class Maps and Match Criteria
To display all class-maps or a specific class map, use the following command.
Dell Networking OS Behavior: An explicit “deny any" rule in a Layer 3 ACL used in a (match any or match all) class-map
creates a "default to Queue 0" entry in the CAM, which causes unintended traffic classification. In the following example, traffic
is classified in two Queues, 1 and 2. Class-map ClassAF1 is “match any,” and ClassAF2 is “match all”.
● Display all class-maps or a specific class map.
EXEC Privilege mode
show qos class-map
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Quality of Service (QoS)