Administrator Guide

Creating a Layer 2 Class Map
All class maps are Layer 3 by default; however, you can create a Layer 2 class map by specifying the layer2 option with the
class-map command.
A Layer 2 class map differentiates traffic according to 802.1p value and/or characteristics defined in a MAC ACL.
Use Step 1 or Step 2 to start creating a Layer 2 class map.
1. Create a match-any class map.
CONFIGURATION mode
class-map match-any
2. Create a match-all class map.
CONFIGURATION mode
class-map match-all
3. Specify your match criteria.
CLASS MAP mode
match mac
After you create a class-map, you are placed in CLASS MAP mode.
Match-any class maps allow up to five access-lists. Match-all class-maps allow only one. You can match against only one
VLAN ID.
4. Link the class-map to a queue.
POLICY MAP mode
service-queue
Applying Layer 2 Match Criteria on a Layer 3 Interface
To process Layer 3 packets that contain a dot1p (IEEE 802.1p) VLAN Layer 2 header, configure VLAN tags on a Layer 3 port
interface which is configured with an IP address but has no VLAN associated with it. You can also configure a VLAN sub-
interface on the port interface and apply a policy map that classifies packets using the dot1p VLAN ID.
To apply an input policy map with Layer 2 match criteria to a Layer 3 port interface, use the service-policy input
policy-name layer 2 command in Interface configuration mode.
To apply a Layer 2 policy on a Layer 3 interface:
1. Configure an interface with an IP address or a VLAN sub-interface
CONFIGURATION mode
Dell(conf)# interface fo 0/0
INTERFACE mode
Dell(conf-if-fo-0/0)# ip address 90.1.1.1/16
2. Configure a Layer 2 QoS policy with Layer 2 (Dot1p or source MAC-based) match criteria.
CONFIGURATION mode
Dell(conf)# policy-map-input l2p layer2
3. Apply the Layer 2 policy on a Layer 3 interface.
INTERFACE mode
Dell(conf-if-fo-0/0)# service-policy input l2p layer2
Applying DSCP and VLAN Match Criteria on a Service Queue
You can configure Layer 3 class maps which contain both a Layer 3 Differentiated Services Code Point (DSCP) and IP VLAN IDs
as match criteria to filter incoming packets on a service queue on the switch.
To configure a Layer 3 class map to classify traffic according to both an IP VLAN ID and DSCP value, use the match ip vlan
vlan-id command in class-map input configuration mode. You can include the class map in a policy map, and apply the class
and policy map to a service queue using the service-queue command. In this way, the system applies the match criteria in a
class map according to queue priority (queue numbers closer to 0 have a lower priority).
Quality of Service (QoS)
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