Configuring a Shared Scheduler and Shaper

Shared scheduling and shaping allows you to allocate separate pools of shared resources to subsets of logical interfaces belonging to the same physical port. You configure this by first creating a traffic-control profile, which specifies a shaping rate and references a scheduler map. You must then share this set of shaping and scheduling resources by applying an instance of the traffic-control profile to a subset of logical interfaces. You can apply a separate instance of the same (or a different) traffic-control profile to another subset of logical interfaces, thereby allocating separate pools of shared resources.

To configure a traffic-control profile, perform the following steps:

1. Include the shaping-rate statement at the [edit class-of-service traffic-control-profiles profile-name] hierarchy level:

   [edit class-of-service traffic-control-profiles profile-name]

   shaping-rate (percent percentage | rate);

   You can configure the shaping rate as a percentage from 1 through 100 or as an absolute rate from 1000 through 160,000,000,000 bits per second (bps). The shaping rate corresponds to a peak information rate (PIR). For more information, see Oversubscribing Interface Bandwidth.

2. Include the scheduler-map statement at the [edit class-of-service traffic-control-profiles profile-name] hierarchy level:

   [edit class-of-service traffic-control-profiles profile-name]

   scheduler-map map-name;

   For information about configuring schedulers and scheduler maps, see Configuring a Scheduler and Configuring the Scheduler Map. Gigabit Ethernet IQ2 interfaces support up to eight forwarding classes and queues. For more information, see Configuring Up to Eight Forwarding Classes.

3. Include the delay-buffer-rate statement at the [edit class-of-service traffic-control-profiles profile-name] hierarchy level:

   [edit class-of-service traffic-control-profiles profile-name]

   delay-buffer-rate (percent percentage | rate);

   You can configure the delay-buffer rate as a percentage from 1 through 100 or as an absolute rate from 1000 through 160,000,000,000 bits per second. The delay-buffer rate controls latency. For more information, see Oversubscribing Interface Bandwidth and Providing a Guaranteed Minimum Rate.

4. Include the guaranteed-rate statement at the [edit class-of-service traffic-control-profiles profile-name] hierarchy level:

   [edit class-of-service traffic-control-profiles profile-name]

   guaranteed-rate (percent percentage | rate);

   You can configure the guaranteed rate as a percentage from 1 through 100 or as an absolute rate from 1000 through 160,000,000,000 bps. The guaranteed rate corresponds to a committed information rate (CIR). For more information, see Providing a Guaranteed Minimum Rate.

   You must now share an instance of the traffic-control profile.

To share an instance of the traffic-control profile, perform the following steps:

1. Include the shared-scheduler statement at the [edit interfaces interface-name] hierarchy level:

   [edit interfaces interface-name]

   shared-scheduler;

   This statement enables logical interfaces belonging to the same physical port to share one set of shaping and scheduling resources.

   Note: On each physical interface, the shared-scheduler and per-unit-scheduler statements are mutually exclusive. Even so, you can configure one logical interface for each shared instance. This effectively provides the functionality of per-unit scheduling.

2. To apply the traffic-control profile to an input interface, include the input-traffic-control-profile and shared-instance statements at the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level:

   [edit class-of-service interfaces interface-name unit logical-unit-number]

   input-traffic-control-profile profile-name shared-instance instance-name;

   These statements are explained in Step Step 3.

3. To apply the traffic-control profile to an output interface, include the output-traffic-control-profile and shared-instance statements at the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level:

   [edit class-of-service interfaces interface-name unit logical-unit-number]

   output-traffic-control-profile profile-name shared-instance instance-name;

   The profile name references the traffic-control profile you configured in Step 1 through Step 4. The shared-instance name does not reference a configuration. It can be any text string you wish to apply to multiple logical interfaces that you want to share the set of resources configured in the traffic-control profile. Each logical interface shares a set of scheduling and shaping resources with other logical interfaces that are on the same physical port and that have the same shared-instance name applied.

   This concept is demonstrated in Examples: Shaping Input and Output Traffic on Ethernet IQ2 Interfaces.

   Note: You cannot include the output-traffic-control-profile statement in the configuration if any of the following statements are included in the logical interface configuration: scheduler-map, shaping-rate, adaptive-shaper, virtual-channel-group.

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