Administrator Guide
• Configure the PFC buffer for all switches in the stack.
CONFIGURATION mode
[no] dcb stack-unit all pfc-buffering pfc-port {1-56} pfc-queues {1-2}
By default, the PFC buffer is enabled on all ports on the stack unit.
• Configure the PFC buffer for all port pipes in a specified stack unit by specifying the port-pipe number,
number of PFC-enabled ports, and number of configured lossless queues.
CONFIGURATION mode
[no] dcb stack-unit stack-unit-id [port-set port-set-id] pfc-buffering pfc-ports
{1-56} pfc-queues {1-2}
Valid stack-unit IDs are 0 to 5.
The only valid port-set ID (port-pipe number) is 0.
Dell Networking OS Behavior:
To achieve lossless PFC operation, the PFC port count and queue number used for the reserved buffer size
that is created must be greater than or equal to the buffer size required for PFC-enabled ports and lossless
queues on the switch.
For the PFC buffer configuration to take effect, you must reload the stack or a specified stack unit (use the
reload command at EXEC Privilege level).
If you configure the PFC buffer on all stack units, delete the startup configuration on both the master and
standby, and reload the stack, the new master (previously standby) generates the following syslog message
for each stack unit when it boots up: PFC_BUFFER_CONFIG_CHANGED is generated for all stack
units
.
Configuring Enhanced Transmission
Selection
ETS provides a way to optimize bandwidth allocation to outbound 802.1p classes of converged Ethernet
traffic.
Different traffic types have different service needs. Using ETS, you can create groups within an 802.1p priority
class to configure different treatment for traffic with different bandwidth, latency, and best-effort needs.
For example, storage traffic is sensitive to frame loss; interprocess communication (IPC) traffic is latency-
sensitive. ETS allows different traffic types to coexist without interruption in the same converged link by:
• Allocating a guaranteed share of bandwidth to each priority group.
• Allowing each group to exceed its minimum guaranteed bandwidth if another group is not fully using its
allotted bandwidth.
To configure ETS and apply an ETS dcb-map to an interface, you must follow the steps described in
Configuring Priority-Based Flow Control.
Data Center Bridging (DCB) 289