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network is used to process. For example, you can assign a higher priority for time-sensitive applications
and a lower priority for other services, such as file transfers. You can configure the amount of buffer
space to be allocated for each priority and the pause or resume thresholds for the buffer. This method of
configuration enables you to effectively manage and administer the behavior of lossless queues.
Example
Dell(conf)#dcb pfc-queues 4
dcb {ets | pfc} enable
Enable priority flow control or enhanced transmission selection on interface.
Syntax
dcb {ets | pfc} enable
● To disable ETS on interface, use “no dcb ets enable” command.
● To disable PFC on interface, use “no dcb pfc enable” command.
Defaults Enable
Command Modes INTERFACE
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.3 (0.1) Introduced on S6000, S4810, and S4820T.
Usage
Information
PFC and ETS are enabled by default on the interfaces when DCB is globally enabled (refer to dcb enable).
In some network topology, you may want to disable PFC on an interface and apply link level flow control;
Similarly you may want to disable ETS on an interface and apply QoS bandwidth configurations.
Limitations
● “dcb-map” CLI on interface is mutually exclusive to “no dcb ets enable” and “no dcb pfc
enable”.
● “pfc priority” CLI is mutually exclusive to “no dcb pfc enable” command.
● Deprecated CLI “dcb-policy input” and “no dcb pfc enable” cannot coexist at interface
level.
● Deprecated CLI “dcb-policy output” and “no dcb ets enable” cannot coexist at interface
level.
service-class buffer shared-threshold-weight
Create a service class and associate the threshold weight of the shared buffer with each of the queues per port in the egress
direction.
Syntax
[No] Service-class buffer shared-threshold-weight {[queue0 number] ||
[queue1 number] || [queue2 number] || [queue3 number] || [queue4 number] ||
[queue5 number] || [queue6 number] || [queue7 number]}
Parameters
buffer Define the shared buffer settings.
shared-
threshold-weight
Specify the weight of a queue for the shared buffer space.
queue 0 to queue
7
To apply the shared-threshold weight, specify the queue number .
number Enter a weight for the queue on the shared buffer as a number in the range of 1 to
11.
394 Data Center Bridging (DCB)