Dell S4048T - Guidelines for Configuring ECN for Classifying and Color-Marking Packets

To configure the weight factor for WRED and ECN capabilities, global buffer pools for multiple queues, and
associating a service class with ECN marking, perform the following:
1 Configure the weight factor for the computation of average-queue size. This weight value applies to
front-end ports.
QOS-POLICY-OUT mode
Dell(conf-qos-policy-out)#wred—profile weight number
2 Configure a WRED profile, and specify the threshold and maximum drop rate.
WRED mode
Dell(conf-wred) #wred—profile thresh-1
Dell(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
Dell(conf-wred) #wred—profile thresh-2
Dell(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.
mode
Dell(conf) #service-pool wred green pool0 thresh-1 pool1 thresh-2
Dell(conf) #service-pool wred yellow pool0 thresh-3 pool1 thresh-4
Dell(conf) #service-pool wred weight pool0 11 pool1 4
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 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.
Quality of Service (QoS) 859