Setup Guide

• You cannot enable PFC and link-level flow control at the same time on an interface.
Applying a DCB Map on a Port
When you apply a DCB map with PFC enabled on a switch interface, a memory buffer for PFC-enabled priority traffic is automatically
allocated. The buffer size is allocated according to the number of PFC-enabled priorities in the assigned map.
To apply a DCB map to an Ethernet port, follow these steps:
Table 19. DCB Map to an Ethernet Port
Step Task Command Command Mode
1
Enter interface configuration mode on an Ethernet port.
interface interface-type }
CONFIGURATION
2
Apply the DCB map on the Ethernet port to configure 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 configured for PFC using the
pfc priority
command or which is already configured for lossless queues
(
pfc no-drop queues command).
dcb-map
name
INTERFACE
Configuring 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 specific dot1p-priorities on individual interfaces without using a DCB map. This type of DCB configuration is useful on interfaces that
require PFC for lossless traffic, but do not transmit converged Ethernet traffic.
Table 20. Configuring PFC without a DCB Map
Step Task Command Command Mode
1 Enter interface configuration mode on an Ethernet port.
interface interface-type}
CONFIGURATION
2 Enable PFC on specified 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 configure PFC using the pfc priority
command on an interface on which a DCB map has
been applied or which is already configured for lossless
queues (pfc no-drop queues command).
pfc priority
priority-
range
INTERFACE
Configuring PFC Asymmetric
The interface is designed to honor incoming pause frames (lossy and lossless) on all priorities. However, the interface will only generate
pause frames on priorities that are configured to be lossless (typically priorities 3 and 4). Any received pause frames are reflected in the
appropriate counters, and PFC watchdog accounts for pause frames on all priorities.
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Data Center Bridging (DCB)