Owners Manual

loss links for Storage Area Network (SAN) traffic that requires no-drop service, while retaining packet-
drop congestion management for Local Area Network (LAN) traffic.
To configure PFC, follow these steps.
1. Create a DCB Map.
CONFIGURATION mode
dcb-map dcb-map-name
The dcb-map-name variable can have a maximum of 32 characters.
2. Create a PFC group to use with a PFC output policy.
CONFIGURATION mode
priority-group group-num {bandwidth bandwidth | strict-priority} pfc on
The range for priority group is from 0 to 7.
Set the bandwidth in percentage. The percentage range is from 1 to 100% in units of 1%.
Committed and peak bandwidth is in megabits per second. The range is from 0 to 40000.
Committed and peak burst size is in kilobytes. Default is 50. The range is from 0 to 10000.
The pfc on command enables priority-based flow control.
3. Specify the dot1p priority-to-priority group mapping for each priority.
priority-pgid dot1p0_group_num dot1p1_group_num ...dot1p7_group_num
Priority group range is from 0 to 7. All priorities that map to the same queue must be in the same
priority group.
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.
Dell Networking OS Behavior: As soon as you apply a DCB policy with PFC enabled on an interface,
DCBx starts exchanging information with PFC-enabled peers. The IEEE802.1Qbb, CEE, and CIN versions
of PFC Type, Length, Value (TLV) are supported. DCBx also validates PFC configurations that are received
in TLVs from peer devices.
NOTE: You cannot enable PFC and link-level flow control at the same time on an interface.
When you apply an input policy to an interface, an error message displays if:
• The PFC dot1p priorities result in more than two lossless port queues globally on the switch.
• Link-level flow control is already enabled. You cannot be enable PFC and link-level flow control at the
same time on an interface.
• In a switch stack, configure all stacked ports with the same PFC configuration.
NOTE: We recommend that you do not use the dcb-policy input, dcb-policy output, dcb-
input, dcb-output, and priority-group commands as those are removed from Release 9.6.
(0.0).
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Data Center Bridging (DCB)