Data Center Bridging: Default Configuration - Dell S4048T Configuration Manual

DCB map is applied. By default, PFC is not applied on specific 802.1p priorities; ETS assigns equal
bandwidth to each 802.1p priority.
As a result, PFC and lossless port queues are disabled on 802.1p priorities, and all priorities are mapped
to the same priority queue and equally share the port bandwidth.
• To change the ETS bandwidth allocation configured for a priority group in a DCB map, do not modify
the existing DCB map configuration. Instead, first create a new DCB map with the desired PFC and ETS
settings, and apply the new map to the interfaces to override the previous DCB map settings. Then,
delete the original dot1p priority-priority group mapping.
If you delete the dot1p priority-priority group mapping (no priority pgid command) before you
apply the new DCB map, the default PFC and ETS parameters are applied on the interfaces. This change
may create a DCB mismatch with peer DCB devices and interrupt network operation.
Data Center Bridging: Default
Configuration
Before you configure PFC and ETS on a switch see the priority group setting taken into account the following
default settings:
DCB is enabled.
PFC and ETS are globally enabled by default.
The default dot1p priority-queue assignments are applied as follows:
Dell(conf)#do show qos dot1p-queue-mapping
Dot1p Priority : 0
Queue : 0
Dell(conf)#
PFC is not applied on specific dot1p priorities.
ETS: Equal bandwidth is assigned to each port queue and each dot1p priority in a priority group.
To configure PFC and ETS parameters on an interface, you must specify the PFC mode, the ETS bandwidth
allocation for a priority group, and the 802.1p priority-to-priority group mapping in a DCB map. No default
PFC and ETS settings are applied to Ethernet interfaces.
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0 0 1 2 3 3
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Data Center Bridging (DCB) 300