PowerConnect B-Series FCX Configuration Guide xvii53-1002266-01QoS for stackable devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .595QoS profile restrictions in an IronStack . . . . . . . . . . . . . . . . . .595QoS behavior for trusting Layer 2 (802.1p) in an IronStack . .595QoS behavior for trusting Layer 3 (DSCP) in an IronStack . . .595QoS behavior on port priority and VLAN priorityin an IronStack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596QoS behavior for 802.1p marking in an IronStack . . . . . . . . .596QoS queues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596Assigning QoS priorities to traffic. . . . . . . . . . . . . . . . . . . . . . . . . . .596Changing a port priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .597Assigning static MAC entries to priority queues. . . . . . . . . . . .597Buffer allocation/threshold for QoS queues . . . . . . . . . . . . . .598802.1p priority override . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .598Configuration notes and feature limitations . . . . . . . . . . . . . .598Enabling 802.1p priority override . . . . . . . . . . . . . . . . . . . . . . .598Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .599Configuring DSCP-based QoS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .599Application notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .599Using ACLs to honor DSCP-based QoS . . . . . . . . . . . . . . . . . . .599Configuring the QoS mappings. . . . . . . . . . . . . . . . . . . . . . . . . . . . .600Default DSCP to internal forwarding priority mappings. . . . . .600Changing the DSCP to internal forwardingpriority mappings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .601Changing the VLAN priority 802.1p to hardwareforwarding queue mappings . . . . . . . . . . . . . . . . . . . . . . . . . . .6028 to 4 queue mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .602Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .603QoS queuing methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .603Selecting the QoS queuing method . . . . . . . . . . . . . . . . . . . . .605Configuring the QoS queues . . . . . . . . . . . . . . . . . . . . . . . . . . .605Viewing QoS settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .608Viewing DSCP-based QoS settings . . . . . . . . . . . . . . . . . . . . . . . . . .608Chapter 18 Configuring Traffic PoliciesTraffic policies overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .611Configuration notes and feature limitations . . . . . . . . . . . . . . . . . .612Maximum number of traffic policies supported on a device . . . . .612Setting the maximum number of traffic policiessupported on a Layer 3 device . . . . . . . . . . . . . . . . . . . . . . . . .613ACL-based rate limiting using traffic policies. . . . . . . . . . . . . . . . . .613Support for fixed rate limiting and adaptive rate limiting . . . .614Configuring ACL-based fixed rate limiting . . . . . . . . . . . . . . . . .614Configuring ACL-based adaptive rate limiting . . . . . . . . . . . . .615Specifying the action to be taken for packets that areover the limit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617
