DELL S6000-ON User Manual

Page of 1100
• 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”.
Create a QoS Policy
There are two types of QoS policies — input and output.
Input QoS policies regulate Layer 3 and Layer 2 ingress traffic. The regulation mechanisms for input QoS 
policies are rate policing and setting priority values.
• Layer 3 — QoS input policies allow you to rate police and set a DSCP or dot1p value. In addition, you 
can configure a drop precedence for incoming packets based on their DSCP value by using a DSCP 
color map. For more information, see 
• Layer 2 — QoS input policies allow you to rate police and set a dot1p value.
Output QoS policies regulate egress traffic. The regulation mechanisms for output QoS policies are 
bandwidth percentage, scheduler strict, rate shaping and WRED.
NOTE: When changing a "service-queue" configuration in a QoS policy map, all QoS rules are 
deleted and re-added automatically to ensure that the order of the rules is maintained. As a result, 
the Matched Packets value shown in the show qos statistics command is reset.
NOTE: To avoid issues misconfiguration causes, Dell Networking recommends configuring either 
DCBX or Egress QoS features, but not both simultaneously. If you enable both DCBX and Egress 
QoS at the same time, the DCBX configuration is applied and unexpected behavior occurs on the 
Egress QoS.
Creating an Input QoS Policy
To create an input QoS policy, use the following steps.
1.
Create a Layer 3 input QoS policy.
CONFIGURATION mode
qos-policy-input
Create a Layer 2 input QoS policy by specifying the keyword layer2 after the qos-policy-input 
command.
2. After you create an input QoS policy, do one or more of the following:
Quality of Service (QoS)
737