Concept Guide

Likewise, in the following conguration, packets with dot1p priority 0–3 are marked as dot1p 7 in the outer tag and queued to Queue 3.
Rate policing is according to qos-policy-input 3. All other packets will have outer dot1p 0 and hence are queued to Queue 1. They are
therefore policed according to qos-policy-input 1.
policy-map-input in layer2
service-queue 1 qos-policy 1
service-queue 3 qos-policy 3
!
qos-policy-input 1 layer2
rate-police 10
!
qos-policy-input 3 layer2
rate-police 30
!
interface GigabitEthernet 1/21
no ip address
switchport
vlan-stack access
vlan-stack dot1p-mapping c-tag-dot1p 0-3 sp-tag-dot1p 7
service-policy input in layer2
no shutdown
Mapping C-Tag to S-Tag dot1p Values
To map C-Tag dot1p values to S-Tag dot1p values and mark the frames accordingly, use the following commands.
1 Allocate CAM space to enable queuing frames according to the C-Tag or the S-Tag.
CONFIGURATION mode
cam-acl l2acl number ipv4acl number ipv6acl number ipv4qos number l2qos number l2pt number
ipmacacl number ecfmacl number {vman-qos | vman-qos-dual-fp} number
• vman-qos: mark the S-Tag dot1p and queue the frame according to the original C-Tag dot1p. This method requires half as many
CAM entries as
vman-qos-dual-fp.
• vman-qos-dual-fp: mark the S-Tag dot1p and queue the frame according to the S-Tag dot1p. This method requires twice as
many CAM entries as
vman-qos and FP blocks in multiples of 2.
The default is: 0 FP blocks for vman-qos and vman-qos-dual-fp.
2 The new CAM conguration is stored in NVRAM and takes eect only after a save and reload.
EXEC Privilege mode
copy running-config startup-config
3 Reload the system.
reload
4 Map C-Tag dot1p values to a S-Tag dot1p value.
INTERFACE mode
vlan-stack dot1p-mapping c-tag-dot1p values sp-tag-dot1p value
Separate C-Tag values by commas. Dashed ranges are permitted.
Dynamic Mode CoS overrides any Layer 2 QoS conguration in case of conicts.
NOTE
: Because dot1p-mapping marks and queues packets, the only remaining applicable QoS conguration is rate metering.
You may use Rate Shaping or Rate Policing.
Service Provider Bridging 809