Juniper EX9200 Series, Features Manual

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excess-burst-size
Syntax excess-burst-size bytes;
Hierarchy Level [edit dynamic-profiles profile-name firewall three-color-policer name single-rate ],
[edit firewall three-color-policer policer-name single-rate ]
Release Information Statement introduced in Junos OS Release 7.4.
Support at the
[edit dynamic-profiles ... single-rate] hierarchy level introduced in Junos
Release OS 11.4.
Statement introduced in Junos OS Release 12.3R2 for EX Series switches.
Description For a single-rate three-color policer, configure the excess burst size (EBS) as a number
of bytes. The EBS allows for moderate periods of bursting traffic that exceeds both the
committed information rate (CIR) and the committed burst size (CBS).
NOTE: When you include the
excess-burst-size
statement in the configuration,
you must also include the
committed-burst-size
and
committed-information-rate
statements at the same hierarchy level.
Traffic that exceeds both the CIR and the CBS is considered nonconforming.
Single-rate three-color policing uses a dual token bucket algorithm to measure traffic
against a single rate limit. Nonconforming traffic is categorized as yellow or red based
on the
excess-burst-size
statement included in the policer configuration.
During periods of traffic that conforms to the CIR, any unused portion of the guaranteed
bandwidth capacity accumulates in the first token bucket, up to the maximum number
of bytes defined by the CBS. If any accumulated bandwidth capacity overflows the first
bucket, the excess accumulates in a second token bucket, up to the maximum number
of bytes defined by the EBS.
A nonconforming traffic flow is categorized yellow if its size conforms to bandwidth
capacity accumulated in the first token bucket. Packets in a yellow flow are marked with
medium-high
packet loss priority (PLP) and then passed through the interface.
A nonconforming traffic flow is categorized red if its size exceeds the bandwidth capacity
accumulated in the second token bucket. Packets in a red traffic flow are marked with
high
PLP and then either passed through the interface or optionally discarded.
Options bytes —Number of bytes. You can specify a value in bytes 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).
Range: 1500 through 100,000,000,000 bytes
Required Privilege
Level
firewall—To view this statement in the configuration.
firewall-control—To add this statement to the configuration.
Copyright © 2016, Juniper Networks, Inc. 212
Traffic Policers Feature Guide for EX9200 Switches