On 7210 SAS-Mxp, when port-based queues are enabled, in addition to marking values, the access egress QoS policy provides an option to define port-based queues and scheduling.
When port-scheduler-mode is enabled, the software uses 8 (eight) egress queues per access port or hybrid port and all the SAPs configured on the port share the 8 (eight) egress queues for traffic sent out of that port. When port-scheduler-mode is enabled, the queue parameters for the access port egress queues are defined using the access egress policies.
Individual queue parameters for a specific queue can be modified using the queue override feature. See Queue overrides for access egress QoS policies on the 7210 SAS-Mxp, 7210 SAS-R6, and 7210 SAS-R12 for more information.
Additionally, the marking values used to mark traffic from different FCs are defined by the remark policy in the access egress policy. Per-SAP marking cannot be used when port-based queuing mode is used. See Access egress QoS policies for 7210 SAS-Mxp, 7210 SAS-R6, and 7210 SAS-R12 for more information about marking behavior with different remark policy types.
On 7210 SAS-Mxp, access egress QoS policies define egress queues and map FC flows to queues, if port-scheduler-mode is enabled. In port-scheduler-mode, the system allocates 8 (eight) queues to access port egress by default. To define a basic access egress QoS policy, the following are required:
a unique access egress QoS policy ID
a QoS policy scope of template or exclusive
See Queue parameters for information about the parameters that can be configured for a queue.
Optional service egress QoS policy elements include specifying a remark policy that defines IEEE 802.1p priority value remarking based on the FC.
On 7210 SAS-Mxp, when port-based queuing is used, the FC-to-queue map is fixed and the queue priority is determined by the queue number, with the higher queue number having the higher priority. The user can configure a queue to be a strict queue to change the scheduling behavior for that queue. See Schedulers on 7210 SAS-Mxp for more information about scheduling.