Dell Networking S6000 System, Справочное руководство

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Default By default, ECN marking is disabled on all queues.
Command
Modes CONFIGURATION mode
Command
History
Version 9.3.0.0 Introduced on the S6000 and Z9000 platforms
Usage
Information You can add or remove ECN marking configuration on a list of queues on all
backplane ports. All of the configured attributes apply to all the backplane ports
and are for each queue. You can configure all the data queues. For Z9000, you can
configure queues 0-3. By default, ECN marking is disabled on all queues. When you
enable wred-ecn, and the number of packets in the queue is below the minimum
threshold, packets are transmitted per the usual WRED treatment. When you
enable wred-ecn, and the number of packets in the queue is between the
minimum threshold and the maximum threshold, one of the following two
scenarios can occur:
• If the transmission endpoints are ECN-capable and traffic is congested, and the
WRED algorithm determines that the packet should have been dropped based
on the drop probability, the packet is transmitted and marked so the routers
know the system is congested and can slow transmission rates.
• If neither endpoint is ECN-capable, the packet may be dropped based on the
WRED drop probability. This behavior is the identical treatment that a packet
receives when WRED is enabled without ECN configured on the router. When
you enable wred-ecn, and the number of packets in the queue is above the
maximum threshold, packets are dropped based on the drop probability. This
behavior is the identical treatment a packet receives when WRED is enabled
without ECN configured on the router.
Example
Dellconf) #service-class wred ecn 0,3-5,7 backplane
DSCP Color Map Commands
The DSCP color map allows you to set the number of specific DSCP values to yellow or red. Traffic
marked as yellow delivers traffic to the egress queue which will either transmit the packet if it has
available bandwidth or drop the packet due to no ability to send. Traffic marked as red (high drop
precedence) is dropped.
dscp
Sets the number of specific DSCP values for a color map profile to yellow or red.
Syntax
dscp {yellow | red} [ list-dscp-values ]
To remove a color policy map profile, use the
no dscp {yellow | red}
[ dscp-list ]
command.
Quality of Service (QoS)
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