Reference Guide
6 Enable WRED/ECN on a port.
OS10(config)# interface ethernet 1/1/1
OS10(conf-if-eth1/1/1)# random-detect wred_prof_1
7 Enable WRED/ECN on a service-pool.
OS10(config)# system qos
OS10(config-sys-qos)# random-detect pool 0 wred_prof_1
Congure congestion avoidance for the S4200
NOTE: For the S4200 platform, ECN can be enabled globally only. Also, ECN congurations can be applied only at the queue
level. You cannot congure ECN at interface and service pool levels. In the S4200, if you try to apply the ECN congure at
interface or service pool levels, the conguration is not accepted.
1 Congure WRED prole in the CONFIGURATION mode.
OS10(config)# wred wred_prof_1
2 Congure WRED threshold parameters for dierent colors in the WRED CONFIGURATION mode.
OS10(config-wred)# random-detect color yellow minimum-threshold 100 maximum-threshold 300
drop-probability 40
3 Congure the exponential weight value for the WRED prole in the WRED CONFIGURATION mode.
OS10(config-wred)# random-detect weight 4
4 Congure the ECN threshold parameters in the WRED CONFIGURATION mode.
OS10(config-wred)#random-detect ecn minimum-threshold 100 maximum-threshold 300 drop-
probability 40
5 Exit the WRED CONFIGURATION mode.
OS10(config-wred)#exit
6 Enter QOS POLICY-MAP mode and create a queuing policy type.
OS10(config)#policy-map type queuing pol-map-1
7 Create a QoS class for the queuing policy type.
OS10(config-pmap-queuing)#class default
8 Assign a WRED prole to the specied queue.
OS10(config-pmap-c-que)#random-detect prof1
9 Exit class map and policy map modes.
OS10(config-pmap-c-que)#exit
OS10(config-pmap-queuing)#exit
10 Enter the SYSTEM QOS mode.
OS10(config)#configure system-qos
11 Enable ECN globally.
OS10(config-sys-qos)#random-detect ecn
After you enable ECN globally, ECN marks the CE bit of ECN eld in a packet as ECT.
In the S4200, you can congure separate thresholds for ECT. If ECN is enabled, ECN capable trac (ECT) is marked based on the
congured ECN threshold and non-ECT is dropped based on the WRED thresholds.
Storm control
Trac storms created by packet ooding or other reasons may degrade the performance of the network.
The storm control feature allows you to control unknown unicast, multicast, and broadcast trac on Layer 2 and Layer 3 physical
interfaces.
In the storm control unknown unicast conguration, both the unknown unicast and unknown multicast trac are rate-limited.
680
Quality of service