I
NTERFACE
C
OMMANDS
-7
flowcontrol (3-7)
flowcontrol
This command enables flow control. Use the no form to disable flow
control.
Syntax
[no] flowcontrol
Default Setting
Flow control enabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• Flow control can e liminate frame loss by “blocking” traffic from end
stations or segments connected directly to the switch when its buffers
fill. When enabled, back pressure is used for half-duplex operation and
IEEE 802.3x for full-duplex operation.
• To force flow control on or off (with the flowcontrol or no
flowcontrol command), use the no negotiation command to disable
auto-negotiation on the selected interface.
When using the negotiation command to enable auto-negotiation, the
optimal settings will be determined by the capabilities command. To
enable flow control under auto-negotiation, “flowcontrol” must be
included in the capabilities list for any port
• Avoid using flow control on a port connect ed to a hub unless it is
actually required to solve a problem. Otherwise back pressure jamming
signals may degrade overall performance for the segment attached to
the hub.