Flowcontrol - Cisco Catalyst 3560X-24P Command Reference Manual

flowcontrol

flowcontrol
Use the flowcontrol interface configuration command on the switch stack or on a standalone switch to
set the receive flow-control state for an interface. When flow control send is operable and on for a device
and it detects any congestion at its end, it notifies the link partner or the remote device of the congestion
by sending a pause frame. When flow control receive is on for a device and it receives a pause frame, it
stops sending any data packets. This prevents any loss of data packets during the congestion period.
Use the receive off keywords to disable flow control.
The Catalyst 3650-X and 3560-X switches can receive, but not send, pause frames.
Note
Syntax Description receive
desired
off
on
Defaults The default is flowcontrol receive off.
Command Modes Interface configuration
Command History Release
12.2(53)SE2
Usage Guidelines The switch does not support sending flow-control pause frames.
Note that the on and desired keywords have the same result.
When you use the flowcontrol command to set a port to control traffic rates during congestion, you are
setting flow control on a port to one of these conditions:
•
•
Catalyst 3750-X and 3560-X Switch Command Reference
2-204
flowcontrol receive {desired | off | on}
Set whether the interface can receive flow-control packets from a remote device.
Allow an interface to operate with an attached device that is required to send
flow-control packets or with an attached device that is not required to but can send
flow-control packets.
Turn off the ability of an attached device to send flow-control packets to an interface.
Allow an interface to operate with an attached device that is required to send
flow-control packets or with an attached device that is not required to but can send
flow-control packets.
Modification
This command was introduced.
receive on or desired: The port cannot send pause frames, but can operate with an attached device
that is required to or is able to send pause frames. The port can receive pause frames.
receive off: Flow control does not operate in either direction. In case of congestion, no indication is
given to the link partner, and no pause frames are sent or received by either device.
Chapter 2 Catalyst 3750-X and 3560-X Switch Cisco IOS Commands
OL-21522-02