Dell Force10 E600i FTOS Version 8.4.1.5 Configuration Guide for ExaScale - Page 813

The behavior is similar for trust dot1p fallback in a Layer2 input policy map; the dot1p-to-queue mapping is according to Table 44-6, "Default dot1p to Queue Mapping," in Quality of Service. To enable Fall Back to trust diffserve or dot1p: Task Command Syntax Classify packets according to their DSCP value as a secondary option in trust {diffserve | case no match occurs against the configured class maps. dot1p} fallback Command Mode POLICY-MAP-IN Mapping dot1p values to service queues c s Mapping dot1p values to service queues is available only on platforms: On the C-Series and S-Series all traffic is by default mapped to the same queue, Queue 0. If you honor dot1p on ingress, then you can create service classes based the queueing strategy in Table 44-6, "Default dot1p to Queue Mapping," in Quality of Service using the command service-class dynamic dot1p from INTERFACE mode. You may apply this queuing strategy globally by entering this command from CONFIGURATION mode. • All dot1p traffic is mapped to Queue 0 unless service-class dynamic dot1p is enabled on an interface or globally. • Layer 2 or Layer 3 service policies supersede dot1p service classes. Guaranteeing bandwidth to dot1p-based service queues Guarantee a minimum bandwidth to queues globally from CONFIGURATION mode with the command service-class bandwidth-weight. The command is applied in the same way as the bandwidth-weight command in an output QoS policy (refer to Allocate bandwidth to queue). The bandwidth-weight command in QOS-POLICY-OUT mode supersedes the service-class bandwidth-weight command. Apply an input policy map to an interface Apply an input policy map to an interface using the command service-policy input from INTERFACE mode. Specify the keyword layer2 if the policy map you are applying a Layer 2 policy map; in this case, the INTERFACE must be in switchport mode. You can apply the same policy map to multiple interfaces, and you can modify a policy map after you apply it. • You cannot apply a class-map and QoS policies to the same interface. • You cannot apply an input Layer 2 QoS policy on an interface you also configure with vlan-stack access. • If you apply a service policy that contains an ACL to more than one interface, FTOS uses ACL optimization to conserves CAM space. The ACL Optimization behavior detects when an ACL already exists in the CAM and rather than writing it to the CAM multiple times. Quality of Service | 813