Users Guide

CONFIGURATION mode
dcb stack-unit all pfc-buffering pfc-ports 64 pfc-queues 2
NOTE: To save the pfc buering conguration changes, save the conguration and reboot the
system.
NOTE: Dell Networking OS Behavior: DCB is not supported if you enable link-level ow control on one or more interfaces. For
more information, refer to Flow Control Using Ethernet Pause Frames.
Conguring DCB Maps and its Attributes
This topic contains the following sections that describe how to congure a DCB map, apply the congured DCB map to a port, congure
PFC without a DCB map, and congure lossless queues.
DCB Map: Conguration Procedure
A DCB map consists of PFC and ETS parameters. By default, PFC is not enabled on any 802.1p priority and ETS allocates equal bandwidth
to each priority. To congure user-dened PFC and ETS settings, you must create a DCB map.
1 Enter global conguration mode to create a DCB map or edit PFC and ETS settings.
CONFIGURATION mode
dcb-map name
2 Congure the PFC setting (on or o) and the ETS bandwidth percentage allocated to trac in each priority group, or whether the
priority group trac should be handled with strict priority scheduling. You can enable PFC on a maximum of two priority queues on an
interface. Enabling PFC for dot1p priorities makes the corresponding port queue lossless. The sum of all allocated bandwidth
percentages in all groups in the DCB map must be 100%. Strict-priority trac is serviced rst. Afterwards, bandwidth allocated to
other priority groups is made available and allocated according to the specied percentages. If a priority group does not use its
allocated bandwidth, the unused bandwidth is made available to other priority groups.
DCB MAP mode
priority-group group_num {bandwidth percentage | strict-priority} pfc {on | o}
Example: priority-group 0 bandwidth 60 pfc o priority-group 1 bandwidth 20 pfc on priority-group 2 bandwidth 20 pfc on
priority-group 4 strict-priority pfc o
Repeat this step to congure PFC and ETS trac handling for each priority group.
3 Specify the dot1p priority-to-priority group mapping for each priority. Priority-group range: 0 to 7. All priorities that map to the same
queue must be in the same priority group.
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 in which priority group 0 maps to dot1p
priorities 0, 1, and 2; priority group 1 maps to dot1p priority 3; priority group 2 maps to dot1p priority 4; priority group 4 maps to dot1p
priorities 5, 6, and 7.
Data Center Bridging (DCB)
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