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Table 104. Drop Eligibility Behavior (continued)
Ingress Egress DEI Disabled DEI Enabled
Trunk Port Trunk Port Retain inner tag CFI Retain inner tag CFI.
Retain outer tag CFI Set outer tag CFI to 0.
Access Port Trunk Port Retain inner tag CFI Retain inner tag CFI
Set outer tag CFI to 0 Set outer tag CFI to 0
To enable drop eligibility globally, use the following command.
● Make packets eligible for dropping based on their DEI value.
CONFIGURATION mode
dei enable
By default, packets are colored green, and DEI is marked 0 on egress.
Honoring the Incoming DEI Value
To honor the incoming DEI value, you must explicitly map the DEI bit to an Dell EMC Networking OS drop precedence.
Precedence can have one of three colors.
Precedence
Description
Green High-priority packets that are the least preferred to be dropped.
Yellow Lower-priority packets that are treated as best-effort.
Red Lowest-priority packets that are always dropped (regardless of congestion status).
● Honor the incoming DEI value by mapping it to an Dell EMC Networking OS drop precedence.
INTERFACE mode
dei honor {0 | 1} {green | red | yellow}
You may enter the command once for 0 and once for 1.
Packets with an unmapped DEI value are colored green.
To display the DEI-honoring configuration, use the show interface dei-honor [interface slot/port/subport]
in EXEC Privilege mode.
DellEMC#show interface dei-honor
Default Drop precedence: Green
Interface CFI/DEI Drop precedence
---------------------------------------
Te 1/1/1 0 Green
Te 1/1/1 1 Yellow
Te 2/9/1 1 Red
Te 2/10/1 0 Yellow
Marking Egress Packets with a DEI Value
On egress, you can set the DEI value according to a different mapping than ingress.
For ingress information, refer to Honoring the Incoming DEI Value.
To mark egress packets, use the following command.
● Set the DEI value on egress according to the color currently assigned to the packet.
INTERFACE mode
dei mark {green | yellow} {0 | 1}
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