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priority-group 2 bandwidth 20 pfc on
priority-group 4 strict-priority pfc off
3. Specify the priority group ID number to handle VLAN traffic for each dot1p class-of-service: from 0 through 7.
DCB MAP mode
priority-pgid dot1p0_group_num dot1p1_group_num dot1p2_group_num dot1p3_group_num
dot1p4_group_num dot1p5_group_num dot1p6_group_num dot1p7_group_num
Leave a space between each priority group number.
For example: priority-pgid 0 0 0 1 2 4 4 4.
Where dot1p priorities 0, 1, and 2 are mapped to priority group 0; dot1p priority 3 is mapped to priority group 1; dot1p priority
4 is mapped to priority group 2; dot1p priorities 5, 6, and 7 are mapped to priority group 4.
NOTE: All priorities that map to the same egress queue must be in the same priority group.
Important Points to Remember
● If you remove a dot1p priority-to-priority group mapping from a DCB map (the no priority pgid command), the PFC
and ETS parameters revert to their default values on the interfaces on which the 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 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 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 (the 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.
Applying a DCB Map on Server-Facing Ethernet Ports
You can apply a DCB map only on a physical Ethernet interface and can apply only one DCB map per interface.
1. Enter the interface Configuration mode on a server-facing port or port channel to apply a DCB map.
CONFIGURATION mode
interface {tengigabitEthernet slot/port | fortygigabitEthernet slot/port}
NOTE:
You cannot apply a DCB map on a port channel. However, you can apply a DCB map on the ports that are
members of the port channel.
2. Apply the DCB map on an Ethernet port or port channel.
INTERFACE mode
dcb-map name
The port is configured with the PFC and ETS settings in the DCB map.
For example:
Dell# interface tengigabitEthernet 0/0
Dell(config-if-te-0/0)# dcb-map SAN_DCB1
To apply a DCB map to more than one port or port channel, repeat this step.
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