Dell S4820T, Configuration Manual

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• Classification based on DSCP only
• Classification based on ECN only
• Classification based on ECN and DSCP concurrently
You can now use the set-color yellow keyword with the match ip access-group command to mark the
color of the traffic as ‘yellow’ would be added in the ‘match ip’ sequence of the class-map configuration.
By default, all packets are considered as ‘green’ (without the rate-policer and trust-diffserve
configuration) and hence support would be provided to mark the packets as ‘yellow’ alone will be
provided.
By default Dell Networking OS drops all the ‘RED’ or ‘violate’ packets.
The following combination of marking actions to be specified match sequence of the class-map
command:
• set a new DSCP for the packet
• set the packet color as ‘yellow’
• set the packet color as ‘yellow’ and set a new DSCP for the packet
This marking action to set the color of the packet is allowed only on the ‘match-any’ logical operator of
the class-map.
This marking-action can be configured for all of the below L3 match sequence types:
• match ip access-group
• match ip dscp
• match ip precedence
• match ip vlan
Sample configuration to mark non-ecn packets as “yellow” with single traffic
class
Consider the use case where the packet with DSCP value “40” need to be enqueued in queue#2 and
packets with DSCP value as 50 need to be enqueued in queue#3. And all the packets with ecn value as ‘0’
must be marked as ‘yellow’.
The above requirement can be achieved using either of the two approaches.
The above requirement can be achieved using either of the two approaches.
Approach without explicit ECN match qualifiers for ECN packets:
!
ip access-list standard dscp_50
seq 5 permit any dscp 50
!
ip access-list standard dscp_40
seq 5 permit any dscp 40
!
ip access-list standard dscp_50_non_ecn
seq 5 permit any dscp 50 ecn 0
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Quality of Service (QoS)