Mapping C-Tag To S-Tag Dot1P Values - Dell S6100 Configuration Manual

NOTE: The ability to map incoming C-Tag dot1p to any S-Tag dot1p requires installing up to eight entries in the Layer 2 QoS and
Layer 2 ACL table for each configured customer VLAN. The scalability of this feature is limited by the impact of the 1:8 expansion
in these content addressable memory (CAM) tables.
Dell Networking OS Behavior: For Option A shown in the previous illustration, when there is a conflict between the queue selected by
Dynamic Mode CoS (vlan-stack dot1p-mapping) and a QoS configuration, the queue selected by Dynamic Mode CoS takes precedence.
However, rate policing for the queue is determined by QoS configuration. For example, the following access-port configuration maps all
traffic to Queue 0:
vlan-stack dot1p-mapping c-tag-dot1p 0-7 sp-tag-dot1p 1
However, if the following QoS configuration also exists on the interface, traffic is queued to Queue 0 but is policed at 40Mbps (qos-
policy-input for queue 3) because class-map "a" of Queue 3 also matches the traffic. This is an expected behavior.
Examples of QoS Interface Configuration and Rate Policing
policy-map-input in layer2
service-queue 3 class-map a qos-policy 3
!
class-map match-any a layer2
match mac access-group a
!
mac access-list standard a
seq 5 permit any
!
qos-policy-input 3 layer2
rate-police 40
Likewise, in the following configuration, 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 TenGigabitEthernet 1/1/2/1
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 {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.
Service Provider Bridging 773