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 andLayer 2 ACL table for each configured customer VLAN. The scalability of this feature is limited by the impact of the 1:8 expansionin 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 byDynamic 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 alltraffic to Queue 0:vlan-stack dot1p-mapping c-tag-dot1p 0-7 sp-tag-dot1p 1However, 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 Policingpolicy-map-input in layer2service-queue 3 class-map a qos-policy 3!class-map match-any a layer2match mac access-group a!mac access-list standard aseq 5 permit any!qos-policy-input 3 layer2rate-police 40Likewise, 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 aretherefore policed according to qos-policy-input 1.policy-map-input in layer2service-queue 1 qos-policy 1service-queue 3 qos-policy 3!qos-policy-input 1 layer2rate-police 10!qos-policy-input 3 layer2rate-police 30!interface TenGigabitEthernet 1/1/2/1no ip addressswitchportvlan-stack accessvlan-stack dot1p-mapping c-tag-dot1p 0-3 sp-tag-dot1p 7service-policy input in layer2no shutdownMapping C-Tag to S-Tag dot1p ValuesTo 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 modecam-acl l2acl number ipv4acl number ipv6acl number ipv4qos number l2qos number l2pt numberipmacacl 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 manyCAM entries as vman-qos-dual-fp.806 Service Provider Bridging
