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2. Configure the PFC setting (on or off) and the ETS bandwidth percentage allocated to traffic in each priority group or
whether priority group traffic should be handled with strict priority scheduling.
DCB MAP mode
priority-group group_num {bandwidth percentage | strict-priority} pfc {on | off}
3. Specify the priority group ID number to handle VLAN traffic for each dot1p class-of-service: 0 through 7. Leave a space
between each priority group number.
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
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.
● 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.
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 Interface Configuration mode on a server-facing port to apply a DCB map.
CONFIGURATION mode
interface tengigabitEthernet slot/port
2. Apply the DCB map on an Ethernet port. Repeat this step to apply a DCB map to more than one port.
INTERFACE mode
dcb-map name
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 1 2 3 4 5 6 7
Queue : 0 0 0 1 2 3 3 3
Dell(conf)#
NOTE: In Dell Networking OS we support 4 data queues.
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.
Data Center Bridging (DCB)
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