HP StorageWorks 1606 Brocade Fabric OS Administrator's Guide v6.3.0 (53-100133 - Page 458

18 QoS: SID/DID traffic prioritization QoS: SID/DID traffic prioritization SID/DID traffic prioritization is a licensed feature that allows you to categorize the traffic flow between a given host and target as having a high or low priority. For example, you could assign online transaction processing (OLTP) to high priority and backup traffic to low priority. All flows without QoS prioritization are considered medium priority. High, medium, and low priority flows are allocated to different virtual channels (VCs). High priority flows receive more VCs than medium priority flows, which receive more VCs than low priority flows. The virtual channels are allocated as shown in Table 81. TABLE 81 Priority Virtual channels assigned to QoS priority Number of VCs VCs assigned High priority 5 Medium priority 4 Low priority 2 10, 11, 12, 13, 14 2, 3, 4, 5 8, 9 NOTE If there is a single low priority flow to a destination ID (DID) and several medium priority flows to that same DID, then it is possible that the medium priority flows would have less bandwidth because they have to share the medium priority VCs, whereas the low priority flow would have a separate VC. SID/DID traffic prioritization is a licensed feature. An Adaptive Networking license must be installed on every switch that is in the path between a given configured device pair. QoS zones You assign high or low priority (QoS level) using a QoS zone. A QoS zone is a special zone that indicates the priority of the traffic flow between a given host/target pair. The members of a QoS zone are the host/target pairs. QoS zones can contain WWN members (WWNN or WWPN) or Domain, Index (D,I) members. If you use D,I notation in your QoS zones, see "Limitations and restrictions for traffic prioritization" on page 420 for some considerations you should be aware of. A QoS zone has a special name to differentiate it from a regular zone. The format of the QoS zone name is as follows: For high priority: For low priority: QOSHid_xxxxx QOSLid_xxxxx where id is a flow identifier that designates a specific virtual channel for the traffic flow and xxxxx is the user-defined portion of the name. For example, the following are valid QoS zone names: QOSH3_HighPriorityTraffic QOSL1_LowPriorityZone The switch automatically sets the priority for the "host,target" pairs specified in the zones based on the priority level (H or L) in the zone name. 416 Fabric OS Administrator's Guide 53-1001336-01