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Table 18. DCB Map to an Ethernet Port
Step Task Command Command Mode
1
Enter interface conguration mode on an Ethernet port.
interface interface-type }
CONFIGURATION
2
Apply the DCB map on the Ethernet port to congure it with
the PFC and ETS settings in the map; for example:
DellEMC# interface tengigabitEthernet 1/1
DellEMC(config-if-te-1/1/1)# dcb-map
SAN_A_dcb_map1 Repeat Steps 1 and 2 to apply a DCB map
to more than one port.
You cannot apply a DCB map on an interface that has been
already congured for PFC using the pfc priority
command or which is already congured for lossless queues
(pfc no-drop queues command).
dcb-map name
INTERFACE
Conguring PFC without a DCB Map
In a network topology that uses the default ETS bandwidth allocation (assigns equal bandwidth to each priority), you can also enable PFC
for specic dot1p-priorities on individual interfaces without using a DCB map. This type of DCB conguration is useful on interfaces that
require PFC for lossless trac, but do not transmit converged Ethernet trac.
Table 19. Conguring PFC without a DCB Map
Step Task Command Command Mode
1 Enter interface conguration mode on an Ethernet port.
interface interface-type}
CONFIGURATION
2 Enable PFC on specied priorities. Range: 0-7. Default:
None.
Maximum number of lossless queues supported on an
Ethernet port: 2.
Separate priority values with a comma. Specify a priority
range with a dash, for example: pfc priority 3,5-7
1 You cannot congure PFC using the pfc priority
command on an interface on which a DCB map has
been applied or which is already congured for lossless
queues (pfc no-drop queues command).
pfc priority priority-
range
INTERFACE
Priority-Based Flow Control Using Dynamic Buer
Method
In a data center network, priority-based ow control (PFC) manages large bursts of one trac type in multiprotocol links so that it does not
aect other trac types and no frames are lost due to congestion. When PFC detects congestion on a queue for a specied priority, it
sends a pause frame for the 802.1p priority trac to the transmitting device.
Pause and Resume of Trac
The pause message is used by the sending device to inform the receiving device about a congested, heavily-loaded trac state that has
been identied. When the interface of a sending device transmits a pause frame, the recipient acknowledges this frame by temporarily
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Data Center Bridging (DCB)