Dell S4820T, Configuration Manual

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Honor dot1p You can honor dot1p priorities in ingress traffic at the port or global switch level
(refer to Default dot1p to Queue Mapping) using the
service-class dynamic
dot1p
command in INTERFACE configuration mode.
Layer 2 class
maps You can use dot1p priorities to classify traffic in a class map and apply a service
policy to an ingress port to map traffic to egress queues.
NOTE: Dell Networking does not recommend mapping all ingress traffic to a single queue when
using PFC and ETS. However, Dell Networking does recommend using Ingress traffic classification
using the
service-class dynamic dot1p
command (honor dot1p) on all DCB-enabled
interfaces. If you use L2 class maps to map dot1p priority traffic to egress queues, take into account
the default dot1p-queue assignments in the following table and the maximum number of two
lossless queues supported on a port (refer to
Configuring Lossless Queues ).
Although Dell Networking OS allows you to change the default dot1p priority-queue assignments
(refer to
Setting dot1p Priorities for Incoming Traffic ), DCB policies applied to an interface may
become invalid if you reconfigure dot1p-queue mapping. If the configured DCB policy remains
valid, the change in the dot1p-queue assignment is allowed.
NOTE: Although, each port on the S4810, S4820T, and S5000 devices support 8 QoS queues, you
can configure only 4 QoS queues (0-3) to manage data traffic. The remaining 4 queues (4-7) are
reserved for control traffic.
dot1p Value in the
Incoming Frame Egress Queue Assignment
0 0
1 0
2 0
3 1
4 2
5 3
6 3
7 3
dot1p Value in the
Incoming Frame Egress Queue Assignment
0 2
1 0
2 1
3 3
4 4
5 5
6 6
7 7
Data Center Bridging (DCB)
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