Displaying Default And Configured Wred Profiles; Displaying Wred Drop Statistics; Pre-Calculating Available Qos Cam Space - Dell Z9000 Configuration Manual

• If you do not configure Dell Networking OS to honor DSCP values on ingress (refer to
Values on Ingress Packets), all traffic defaults to green drop precedence.
• Assign a WRED profile to either yellow or green traffic.
QOS-POLICY-OUT mode
wred

Displaying Default and Configured WRED Profiles

To display the default and configured WRED profiles, use the following command.
• Display default and configured WRED profiles and their threshold values.
EXEC mode
show qos wred-profile

Displaying WRED Drop Statistics

To display WRED drop statistics, use the following command.
• Display the number of packets Dell Networking OS the WRED profile drops.
EXEC Privilege mode
show qos statistics

Pre-Calculating Available QoS CAM Space

Pre-calculating available QoS CAM space is supported on the Z9000 platform.
Before Dell Networking OS version 7.3.1, there was no way to measure the number of CAM entries a
policy-map would consume (the number of CAM entries that a rule uses is not predictable; from 1 to 16
entries might be used per rule depending upon its complexity). Therefore, it was possible to apply to an
interface a policy-map that requires more entries than are available. In this case, the system writes as
many entries as possible, and then generates an CAM-full error message (shown in the following
example). The partial policy-map configuration might cause unintentional system behavior.
%EX2YD:12 %DIFFSERV-2-DSA_QOS_CAM_INSTALL_FAILED: Not enough space in L3
Cam(PolicyQos) for class 2 (TeGi 12/20) entries on portpipe 1
The test cam-usage command allows you to verify that there are enough available CAM entries before
applying a policy-map to an interface so that you avoid exceeding the QoS CAM space and partial
configurations. This command measures the size of the specified policy-map and compares it to the
available CAM space in a partition for a specified port-pipe.
Test the policy-map size against the CAM space for a specific port-pipe or all port-pipes using these
commands:
•
test cam-usage service-policy input policy-map {stack-unit } number port-set
number
•
test cam-usage service-policy input policy-map {stack-unit } all
The output of this command, shown in the following example, displays:
• The estimated number of CAM entries the policy-map will consume.
662
Honoring DSCP
Quality of Service (QoS)