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Associating the Scheduler Map and a Shaping Rate with a Physical Interface

For IQ PICs, you can configure physical interfaces to shape traffic based on the rate-limited bandwidth of the total interface bandwidth. This allows you to shape the output of the physical interface, so that the interface transmits less traffic than it is physically capable of carrying.

If you do not configure a shaping rate on the physical interface, the default physical interface bandwidth is based on the channel bandwidth and the time slot allocation.

Note: The shaping-rate statement cannot be applied to a physical interface on J-series routing platforms.

To configure shaping on the interface, include the shaping-rate statement at the [edit class-of-service interfaces interface-name] hierarchy level:



[edit class-of-service interfaces interface-name]

shaping-rate rate;

You can specify a peak bandwidth rate in bps, either as a complete decimal number or as a decimal number followed by the abbreviation k (1000), m (1,000,000), or g (1,000,000,000). For physical interfaces, the range is from 1000 through 160,000,000,000 bps. (For logical interfaces, the range is 1000 through 32,000,000,000 bps.) The sum of the bandwidths you allocate to all physical interfaces on a PIC must not exceed the bandwidth of the PIC.

Note: For MX-series Ethernet Services routers, the shaping rate value for the physical interface at the [edit class-of-service interfaces interface-name] hierarchy level must be a minimum of 160 kbps.

If you configure a shaping rate that exceeds the physical interface bandwidth, the new configuration is ignored, and the previous configuration remains in effect. For example, if you configure a shaping rate that is 80 percent of the physical interface bandwidth, then change the configuration to 120 percent of the physical interface bandwidth, the 80 percent setting remains in effect. This holds true unless the PIC is restarted, in which case the default bandwidth goes into effect. As stated previously, the default bandwidth is based on the channel bandwidth and the time slot allocation.

Optionally, you can instead configure scheduling and rate shaping on logical interfaces, as described in Associating the Scheduler Map and a Shaping Rate with a DLCI or VLAN. In general, logical and physical interface traffic shaping is mutually exclusive. You can include the shaping-rate statement at the [edit class-of-service interfaces interface-name] hierarchy level or the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level, but not both. For Gigabit Ethernet IQ PICs only, you can configure hierarchical traffic shaping, meaning the shaping is performed on both the physical interface and the logical interface. For more information, see Configuring Hierarchical Input Shapers.

To view the results of your configuration, issue the following show commands:

show class-of-service interface interface-name
show interfaces interface-name extensive
show interfaces queue

For more information, see the following sections:

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