Service Manual

○ SYN
○ PSH
○ RST
○ URG
In the existing software, ECE/CWR TCP flag qualifiers are not supported.
● Because this functionality forcibly marks all the packets matching the specific match criteria as ‘yellow’, Dell EMC
Networking OS does not support Policer based coloring and this feature concurrently.
● 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 DSCP
Color Maps.
● 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 EMC 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:
Configuring Policy-Based Rate Policing
Setting a dot1p Value for Egress Packets
Quality of Service (QoS)
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