Addendum

DCB map is applied. By default, PFC is not applied on specific 802.1p priorities; ETS assigns equal
bandwidth to each 802.1p priority.
As a result, PFC and lossless port queues are disabled on 802.1p priorities, and all priorities are
mapped to the same priority queue and equally share port bandwidth.
• To change the ETS bandwidth allocation configured for a priority group in a DCB map, do not modify
the existing DCB map configuration. Instead, first create a new DCB map with the desired PFC and
ETS settings and apply the new map to the interfaces to override the previous DCB map settings. Then
delete the original dot1p priority-priority group mapping.
If you delete the dot1p priority-priority group mapping (no priority pgid command) before you apply
the new DCB map, the default PFC and ETS parameters are applied on the interfaces. This change
may create a DCB mismatch with peer DCB devices and interrupt network operation.
Applying a DCB Map on a Port
When you apply a DCB map with PFC enabled on an S6000 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:
Step Task Command Command Mode
1
Enter interface configuration mode on an
Ethernet port.
interface
{tengigabitEthernet slot/
port | fortygigabitEthernet
slot/port}
CONFIGURATION
2
Apply the DCB map on the Ethernet port to
configure it with the PFC and ETS settings in
the map; for example:
FTOS# interface tengigabitEthernet 0/0
FTOS(config-if-te-0/0)# 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
which 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 specified dot1p-priorities on individual interfaces without using a
DCB map. This type of DCB configuration is useful on interfaces which require PFC for lossless traffic but
do not transmit converged Ethernet traffic.
Step Task Command Command Mode
1 Enter interface configuration mode on an
Ethernet port.
interface
{tengigabitEthernet slot/
port | fortygigabitEthernet
slot/port}
CONFIGURATION
2 Enable PFC on specified priorities. Range:
0-7. Default: None.
pfc priority priority-range INTERFACE
534
Data Center Bridging (DCB)