Dell S4148U-ON OS10 Enterprise Edition User Guide Release 10.4.0E R2 - Page 625

Total Rx PFC Frames: 0 Total Tx PFC frames: 587236 Cos Rx Tx 0 0 0 1 0 0 2 0 0 3 0 587236 4 0 0 5 0 0 6 0 0 7 0 0 Supported Releases 10.3.0E or later Enhanced transmission selection Enhanced transmission selection (ETS) provides customized bandwidth allocation to 802.1p classes of traffic. Assign different amounts of bandwidth to traffic classes (Ethernet, FCoE, or iSCSI) that require different bandwidth, latency, and best-effort treatment during network congestion. ETS divides traffic into different priority groups using their 802.1p priority value. To ensure that each traffic class is correctly prioritized and receives required bandwidth, configure bandwidth and queue scheduling for each priority group. You can allocate more bandwidth to a priority group to prioritize low-latency storage and server-cluster traffic. Allocate less bandwidth to a different priority group to rate-limit best-effort LAN traffic. ETS configuration notes • ETS is supported on L2 802.1p priority (dot1p 0 to 7) and L3 DSCP (0 to 63) traffic. FCoE traffic uses dot1p priority 3 - iSCSI storage traffic uses dot1p priority 4. • Apply these maps and policies on interfaces: • Trust maps - OS10 interfaces do not honor the L2 and L3 priority fields in ingress traffic by default. Create a trust map to honor dot1p and DSCP classes of lossless traffic. A trust map does not change ingress dot1p and DSCP values in egress flows. In a trust map, assign a qos-group (traffic class) to trusted dot1p/DSCP values. A qos-group number is used only internally to schedule classes of ingress traffic. • QoS map - Create a QoS map to assign trusted dot1p and DSCP traffic classes to lossless queues. • Ingress trust policy - Configure a service policy to trust dot1p values in ingress traffic. Converged data center services 625