HP Cisco Catalyst Blade Switch 3020 Cisco Catalyst Blade Switch 3020 for HP Co - Page 119

flowcontrol

Page 119 highlights

Chapter 2 Cisco Catalyst Blade Switch 3020 for HP Cisco IOS Commands flowcontrol flowcontrol Use the flowcontrol interface configuration command 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. flowcontrol receive {desired | off | on} Note The switch can receive, but not send, pause frames. Syntax Description 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. Defaults The default is flowcontrol receive off. Command Modes Interface configuration Command History Release 12.2(25)SEF Modification This command was introduced. 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: • 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. OL-8916-01 Cisco Catalyst Blade Switch 3020 for HP Command Reference 2-91

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Cisco Catalyst Blade Switch 3020 for HP Command Reference
OL-8916-01
Chapter 2
Cisco Catalyst Blade Switch 3020 for HP Cisco IOS Commands
flowcontrol
flowcontrol
Use the
flowcontrol
interface configuration command 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.
flowcontrol receive
{
desired
|
off
|
on
}
Note
The switch can receive, but not send, pause frames.
Syntax Description
Defaults
The default is
flowcontrol receive off
.
Command Modes
Interface configuration
Command History
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:
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.
receive
Set whether the interface can receive flow-control packets from a remote device.
desired
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.
off
Turn off the ability of an attached device to send flow-control packets to an interface.
on
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.
Release
Modification
12.2(25)SEF
This command was introduced.