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Quality of Service (QoS)
The Dell Networking operating software commands for quality of service (QoS) include traffic conditioning and congestion
control. QoS commands are not universally supported on all Dell Networking Products.
Topics:
• Global Configuration Commands
• Per-Port QoS Commands
• Policy-Based QoS Commands
Global Configuration Commands
There are only two global configuration QoS commands.
qos-rate-adjust
By default, while rate limiting, policing, and shaping, the system does not include the Preamble, SFD, or the IFG fields. These
fields are overhead; only the fields from MAC destination address to the CRC are used for forwarding and are included in
these rate metering calculations. You can optionally include overhead fields in rate metering calculations by enabling QoS Rate
Adjustment.
Syntax
qos-rate-adjustment overhead-bytes
Parameters
overhead-bytes Include a specified number of bytes of packet overhead to include in rate limiting,
policing, and shaping calculations. The range is from 1 to 31.
Defaults QoS rate adjustment is disabled by default, and no qos-rate-adjust is listed in the running-
configuration
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.
service-class dot1p-mapping
Configure a service-class criterion based on a dot1p value.
Syntax
service-class dot1p-mapping {dot1p0 value | dot1p1 value | dot1p2 queue |
dot1p3 value | dot1p4 value| dot1p5 value | dot1p6 value | dot1p7 value}
Parameters
value Enter a dot1p list number and value. The list number range is from 0 to 7. The range
is from 0 to 3.
Defaults For each dot1p Priority, the default CoS queue value is:
● dot1p CoS Queue
0 0-7
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940 Quality of Service (QoS)