Configuring Tos-Based Qos; Enabling Tos-Based Qos; Specifying Trust Level; Enabling Marking - Dell PowerConnect B-RX Configuration Manual

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Configuring ToS-based QoS

Configuring ToS-based QoS
To configure ToS-based QoS, perform the following tasks:
•

Enabling ToS-based QoS

To enable ToS-based QoS on an interface, enter the following command at the configuration level
for the interface.
BigIron RX(config-if-e1000-1/1)# qos-tos
Syntax: [no] qos-tos

Specifying trust level

If a packet arrives on the interface with either a COS, DSCP, or COS and DSCP priority level, the
trust level specifies which of these priorities you want to accept. If you disable trust level, the
priority will default to a criteria other than the COS or DSCP priority.
To set the trust level for an interface to dscp, enter the following command at the configuration
level for the interface.
BigIron RX(config-if-e1000-1/1)# qos-tos trust dscp
Syntax: [no] qos-tos trust cos | dscp
The cos | dscp parameter specifies the trust level.
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•

Enabling marking

This command enables marking of the 802.1p field or the DSCP field in the ToS byte of an IP
header.
Syntax: [no] qos-tos mark cos | dscp
The cos | dscp parameter specifies the type of marking.
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Enable ToS-based QoS on an interface. Once you enable the feature on an individual interface,
you can configure the trust level and marking for traffic that is received on that interface as
described:
•
Specify the trust level for packets received on the interface.
•
Enable marking of packets received on the interface.
cos – The device uses the 802.1p (CoS) priority value in the packet's Ethernet frame header to
determine the packet's internal forwarding priority. This is the default state and is in effect
even Qos-ToS is enabled on a port.
dscp – The device uses the six most-significant bits in the packet's ToS field and interprets
them as a DSCP value to determine the packet's internal forwarding priority.
cos – The device changes the outbound packet's 802.1p priority value to match the results of
the device's QoS mapping from the specified trust level.
dscp – The device changes the outbound packet's DSCP value to match the results of the
device's QoS mapping from the specified trust level.
BigIron RX Series Configuration Guide
53-1002253-01