any manually configured information. Interfaces not enabled for PFC ignore
received PFC frames.
◆
PFC is configurable on full duplex interfaces only. To enable PFC on a LAG, the
member interfaces must have the same configuration.
◆
When PFC is enabled on an interface, it will be automatically disabled for
IEEE 802.3 flow control. Any flow control frames received on a PFC enabled
interface are ignored. When PFC is disabled on an interface, it defaults to
IEEE 802.3 flow control.
Example
The following example sets port 5 to use PFC auto-negotiation mode.
Console(config)#interface ethernet 1/5
Console(config-if)#pfc mode auto
Console(config-if)#
pfc priority
Use this command to enable PFC for specified priorities. Use the no form to disable
PFC for specified priorities.
Syntax
[no] pfc priority enable priority-list
priority-list – Priority identifier, specified as a single number, a range of
consecutive numbers separated by a hyphen, or multiple numbers
separated by commas. (Range: 0-7)
Default Setting
Enabled for CoS value 3
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
◆
If a priority list has already been created by this command, then any priorities
specified by subsequent commands are added the existing list.
◆
When PFC is enabled, the interface will not pause any CoS priority frames
unless there is at least one pause priority set by this command.
◆
Each priority is configured as drop (PFC disabled) or no-drop (PFC enabled). If a
priority designated as no-drop is congested, that priority is paused. The same
no-drop priorities must be configured across the network in order to ensure
end-to-end lossless behavior. VLAN tagging also needs to be turned on in order
to carry the PFC priority settings through the network.
Chapter 21
Priority-based Flow Control Commands
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| Data Center Bridging Commands