Specifications

Chapter 5. IBM System Networking RackSwitch implementation 185
򐂰 Run no qos protocol-packet-control rate-limit-packetqueue <packet queue number
(0-40)> to clear the packet rate configured for the selected packet queue.
򐂰 Run show qos protocol-packet-control information protocol to display the mapping
of protocol packet types to each packet queue number. The status indicates whether the
protocol is running or not running.
򐂰 Run show qos protocol-packet-control information queue to display the packet rate
configured for each packet queue.
Weighted Random Early Detection configuration
Weighted Random Early Detection (WRED) provides congestion avoidance by preemptively
dropping packets before a queue becomes full. The RackSwitch G8264 implementation of
WRED defines TCP and non-TCP traffic profiles on a per-port, per COS queue basis. For
each port, you can define a transmit-queue profile with thresholds that define
packet-drop probability.
To use WRED, run the following commands:
򐂰 Run qos random-detect ecn to enable or disable Explicit Congestion Notification (ECN).
When ECN is on, the switch marks the ECN bit of the packet (if applicable) instead of
dropping the packet. ECN-aware devices are notified of the congestion and those devices
can take corrective actions.
򐂰 Run [no] qos random-detect enable to turn on/off Random Detection and avoidance.
򐂰 Run show qos random-detect to display the current Random Detection and
avoidance parameters.
WRED Transmit Queue configuration
To use WRED Transmit Queue, run the following commands:
򐂰 Run [no] qos random detect transmit-queue <0-7> tcp <min. threshold (1-100)>
<max.threshold (1-100)> <drop rate (1-100)> to configure the WRED thresholds for
TCP traffic. Use the no parameter to clear the WRED threshold value.
򐂰 Run [no] qos random detect transmit-queue <0-7> non-tcp <min. threshold
(1-100)> <max.threshold (1-100)> <drop rate (1-100)> to configure the WRED
thresholds for non-TCP traffic. Use the no parameter to clear the WRED threshold value.
򐂰 Run [no] qos random detect transmit-queue <0-7> enable to set the WRED transmit
queue configuration to on or off.
Important: This feature is supported only on RackSwitch G8264 switches.
Important: ECN functions only on TCP traffic.
Note: This feature is supported only on RackSwitch G8264.