Alcatel-Lucent 7950 Quality Of Service Manual page 261

Extensible routing system
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arbiter-name — The arbiter-name parameter specifies that the policer is intended to become a child to one
of the tiered arbiters with the given arbiter-name where an instance of the policer is created. If the
specified arbiter-name does not exist, the policer will be placed in the orphan state.
Default
weight weight-within-level — The weight weight-within-level keyword and parameter are optional when
executing the parent command. When weight is not specified, a default level of 1 is used in the parent
arbiters priority level. When weight is specified, the weight-within-level parameter must be specified as
an integer value from 1 through 100.
Default
rate
Syntax
rate {max | kilobits-per-second} [cir {max | kilobits-per-second}]
no rate
Context
config>qos>sap-egress>policer
Description
This command is used to configure the policer's metering and optional profiling rates. The metering rate is
used by the system to configure the policer's PIR leaky bucket's decrement rate while the profiling rate
configures the policer's CIR leaky bucket's decrement rate. The decrement function empties the bucket
while packets applied to the bucket attempt to fill it based on the each packets size. If the bucket fills faster
than how much is decremented per packet, the bucket's depth eventually reaches it's exceed (CIR) or violate
(PIR) threshold. The cbs, mbs and high-prio-only commands are used to configure the policer's PIR and
CIR thresholds.
If a packet arrives at the policer while the bucket's depth is less than the threshold associated with the
packet, the packet is considered to be conforming to the bucket's rate. If the bucket depth is equal to or
greater than the threshold, the packet is considered to be in the exception state. For the CIR bucket, the
exception state is exceeding the CIR rate while the PIR bucket's exception state is violating the PIR bucket
rate. If the packet is violating the PIR, the packet is marked red and will be discarded. If the packet is not
red, it may be green or yellow based on the conforming or exceeding state from the CIR bucket.
When a packet is red neither the PIR or CIR bucket depths are incremented by the packets size. When the
packet is yellow the PIR bucket is incremented by the packet size, but the CIR bucket is not. When the
packet is green, both the PIR and CIR buckets are incremented by the packet size. This ensures that
conforming packets impact the bucket depth while exceeding or violating packets do not.
The policer's adaptation-rule command settings are used by the system to convert the specified rates into
hardware timers and decrement values for the policer's buckets.
By default, the policer's metering rate is max and the profiling rate is 0 Kbps (all packets out-of-profile).
The rate settings defined for the policer in the QoS policy may be overridden on an sla-profile or SAP
where the policy is applied.
The no form of this command is used to restore the default metering and profiling rate to a policer.
Parameters
{max | kilobits-per-second} — Specifying the keyword max or an explicit kilobits-per-second parameter
directly following the rate command is required and identifies the policer's metering rate for the PIR
leaky bucket. When the policer is first created, the metering rate defaults to max. The kilobits-per-
7950 XRS Quality of Service Guide
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