flow-control

Enables or disables flow control and flow control negotiation, and advertises flow control.

Syntax

flow-control [ both | generate-only | honor-only ]
no flow-control [ both | generate-only | honor-only ]

Command Default

Flow control is enabled.

Parameters

both

Flow control in PAUSE generation and honoring mode.

generate-only

Flow control in PAUSE generation only mode.

honor-only
Flow control in PAUSE honoring (Default) mode.

Modes

Global configuration mode

Interface configuration mode

Usage Guidelines

The no form of this command disables flow control.

On ICX 7750 devices the default packet-forwarding method is cut-through, in which port flow control (IEEE 802.3x) is not supported but priority-based flow control (PFC) is supported. You can configure the store-and- forward command in global configuration mode to enable the store-and-forward method for packet-forwarding.

The recommended flow control settings when the ICX 7750 switch is set for store-and-forward, are listed below.

Symmetrical flow control Port-based flow control Configuration commands Cut-through (Jumbo enabled) Store-and-Forward (Jumbo Enabled)
disabled honor-only # flow-control honor-only Not Recommended OK
no flow-control-both #no flow-control both OK OK
enabled no flow-control-both

#symmetrical-flow-control enable

# no flow-control both

OK OK
honor-only

# symmetrical-flow-control enable

#flow-control honor-only

Not Recommended OK
generate-only

# symmetrical-flow-control enable

# flow-control generate-only

OK OK
both

# symmetrical-flow-control enable

#flow-control both

Not Recommended OK

By default, when flow control is enabled globally and auto-negotiation is on, flow control is enabled and advertised on 10/100/1000M ports. If auto-negotiation is off or if the port speed was configured manually, flow control is neither negotiated with nor advertised to the peer.

NOTE
Enabling only port auto-negotiation does not enable flow control negotiation. You must use the flow-control neg-on command to enable flow-control negotiation.

Examples

The following example disables flow control globally.

device(config)#no flow-control

The following example enables flow control on ethernet ports 0/1/11 to 0/1/15.

device(config)#interface ethernet 0/1/11 to 0/1/15
device(config-mif-0/1/11-0/1/15)#flow-control

The following example disables flow control on ethernet port 1/1/9.

device(config)# interface ethernet 1/1/9
device(config-if-e1000-1/1/9)no flow-control

History

Release version Command history
8.0.20 This command was modified. Enabling only auto-negotiation does not enable flow-control negotiation.