Administrator Guide

Step Task Command Command Mode
DCB map has been applied or which is already
congured for lossless queues (pfc no-drop
queues command).
Conguring Lossless Queues
DCB also supports the manual conguration of lossless queues on an interface after you disable PFC mode in a DCB map and apply
the map on the interface. The conguration of no-drop queues provides exibility for ports on which PFC is not needed, but lossless
trac should egress from the interface.
Lossless trac egresses out the no-drop queues. Ingress 802.1p trac from PFC-enabled peers is automatically mapped to the no-
drop egress queues.
When conguring lossless queues on a port interface, consider the following points:
• By default, no lossless queues are congured on a port.
• A limit of two lossless queues are supported on a port. If the number of lossless queues congured exceeds the maximum
supported limit per port (two), an error message is displayed. You must re-congure the value to a smaller number of queues.
• If you congure lossless queues on an interface that already has a DCB map with PFC enabled (pfc on), an error message is
displayed.
Step Task Command Command Mode
1 Enter INTERFACE Conguration mode.
interface{tengigabitEther
net slot/port |
fortygigabitEthernet slot/
port}
CONFIGURATION
2
Open a DCB map and enter DCB map conguration
mode.
dcb-map name
INTERFACE
3
Disable PFC.
no pfc mode on
DCB MAP
4
Return to interface conguration mode.
exit
DCB MAP
5
Apply the DCB map, created to disable the PFC
operation, on the interface
dcb-map {name | default}
INTERFACE
6
Congure the port queues that still function as no-drop
queues for lossless trac.
The maximum number of lossless queues globally
supported on a port is 2.
You cannot congure PFC no-drop queues on an
interface on which a DCB map with PFC enabled has
been applied, or which is already congured for PFC
using the pfc priority command.
Range: 0-3. Separate queue values with a comma;
specify a priority range with a dash; for example: pfc no-
drop queues 1,3 or pfc no-drop queues 2-3 Default: No
lossless queues are congured.
pfc no-drop
queuesqueue-range
INTERFACE
Data Center Bridging Exchange Protocol (DCBx)
DCBx allows a switch to automatically discover DCB-enabled peers and exchange conguration information. PFC and ETS use DCBx
to exchange and negotiate parameters with peer devices. DCBx capabilities include:
FC Flex IO Modules
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