Administrator Guide

WRED mode
DellEMC(conf-wred) #wred—profile thresh-1
DellEMC(conf-wred) #threshold min 100 max 200 max-drop-rate 40
3. Configure another WRED profile, and specify the threshold and maximum drop rate.
WRED mode
DellEMC(conf-wred) #wred—profile thresh-2
DellEMC(conf-wred) #threshold min 300 max 400 max-drop-rate 80
4. Create a global buffer pool that is a shared buffer pool accessed by multiple queues when the minimum guaranteed buffers
for the queue are consumed. The platform supports four global service-pools in the egress direction.
mode
DellEMC(conf) #service-pool wred green pool0 thresh-1 pool1 thresh-2
DellEMC(conf) #service-pool wred yellow pool0 thresh-3 pool1 thresh-4
DellEMC(conf) #service-pool wred weight pool0 11 pool1 4
5. Create a service class and associate the threshold weight of the shared buffer with each of the queues per port in the
egress direction.
INTERFACE mode
DellEMC(conf-if-te-0/8)#Service-class buffer shared-threshold-weight
Guidelines for Configuring ECN for Classifying and
Color-Marking Packets
Keep the following points in mind while configuring the marking and mapping of incoming packets using ECN fields in IPv4
headers:
● Currently Dell EMC Networking OS supports matching only the following TCP flags:
○ ACK
○ FIN
○ SYN
○ PSH
○ RST
○ URG
In the existing software, ECE/CWR TCP flag qualifiers are not supported.
● Because this functionality forcibly marks all the packets matching the specific match criteria as ‘yellow’, Dell EMC
Networking OS does not support Policer based coloring and this feature concurrently.
● If single rate two color policer is configured along with this feature, then by default all packets less than PIR would be
considered as “Green” But ‘Green’ packets matching the specific match criteria for which ‘color-marking’ is configured will
be over-written and marked as “Yellow”.
● If two rate three color policer is configured along with this feature then,
○ x < CIR – will be marked as “Green”
○ CIR < x< PIR – will be marked as “Yellow”
○ PIR < x – will be marked as “Red”
But ‘Green’ packets matching the specific match criteria for which ‘color-marking’ is configured will be over-written and marked
as “Yellow”.
716
Quality of Service (QoS)