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strict-priority unicast
Configure a unicast queue as a strict-priority (SP) queue.
Syntax
strict-priority unicast queue number
Parameters
unicast number Enter the keyword unicast then the queue number. The range is from 1 to 3.
Defaults none
Command Modes CONFIGURATION
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
8.3.16.1 Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
After you configure a unicast queue as strict-priority, that particular queue, on the entire chassis, is
treated as a strict-priority queue. Traffic for a strict priority is scheduled before any other
queues are serviced. For example, if you send 100% line rate traffic over the SP queue, it starves all other
queues on the ports on which this traffic is flowing. To assign the strict priority schedule type to egress
queues, use the scheduler strict command in QOS-POLICY-OUT mode. The system OS does not
support bandwidth configuration on strict priority scheduler queues.
When you enable ETS, the egress QoS features in the output QoS policy-map (such as strict
priority unicast <0-3> and scheduler strict), default scheduler for egress queues are
superseded by ETS configurations. This is to provide compatibility with DCBX. Therefore, Dell Networking
OS recommends disabling ETS when you wish to apply these features exclusively. After you disable ETS
on an interface, the configured parameters are applied.
Policy-Based QoS Commands
Policy-based QoS is not supported on logical interfaces, such as port-channels, VLANs, or Loopbacks.
The commands are:
● show qos dcb-map
● show qos dot1p-queue-mapping
bandwidth-percentage
Assign a percentage of weight to the class/queue.
Syntax
bandwidth-percentage percentage
To remove the bandwidth percentage, use the no bandwidth-percentage command.
Parameters
percentage Enter the percentage assignment of weight to the class/queue. The range is from 1
to 100% (granularity 1%).
Defaults none
Command Modes CONFIGURATION (conf-qos-policy-out)
Supported Modes Programmable-Mux (PMUX)
Full-Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
Quality of Service (QoS) 945