Sun Microsystems Sun Fire B1600 Administration, Administration Manual

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4-90 Sun Fire B1600 Blade System Chassis Switch Administration Guide • June 2003
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
■
Flow control can eliminate 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 connected 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.
Example
The following example enables flow control on port NETP7.
Related Commands
negotiation
( 4-86 )
capabilities
(flowcontrol, symmetric) ( 4-87 )
Console(config)# interface ethernet NETP7
Console(config-if)# flowcontrol
Console(config-if)# no negotiation
Console(config-if)#