Specifications

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Catalyst 4500 Se ries S wit ch C is co IO S C om mand R efer ence —Re lease I OS XE 3 .3.0 XO(1 5.1 (1)XO)
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Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
flowcontrol
flowcontrol
To configure a Gigabit Ethernet interface to send or receive pause frames, use the flowcontrol command.
To disable the flow control setting, use the no form of this command.
flowcont ro l {receive | send} {off | on | desired}
no flowcontrol {receive | send} {off | on | desired}
Syntax Description
Defaults The default settings for Gigabit Ethernet interfaces are as follows:
• Sending pause frames is off—N on-oversubscrib ed Gigabit Ethernet in terfaces.
• Receiving pause frames is de sired—Non-oversubsc ribed Gigabit Ether net interfaces.
• Sending pause frames is on— Oversubscribed Giga bit Ethernet interf aces.
• Receiving pause frames is de sired—Oversubscr ibed Gigabit Etherne t interfaces.
Table 2-3 shows the default settings for the modules.
Command Modes Interface configur ation mode
Usage Guidelines The pause frames are special packets that signal a source to stop sending frames for a specific period of
time because the buffers are full.
receive Specifies that the interface processes pause frames.
send Specifies that the interface sends pause frames.
off Prevents a local port f rom receiving and processing pause frames from remote ports o r
from sending pause frames to remote ports.
on Enables a local port to receive and process pause frames from remote ports or send
pause fra mes to re mote po rts.
desired Obtains predictable results whether a remote port is set to on, off, or desired.
Table 2-3 Default Module Settings
Module Ports Send
All modules except
WS-X4418-GB and
WS-X4416-2GB-TX
All ports except for the
oversubscribed ports
Off
WS-X4418-GB Uplink p orts ( 1–2) Off
WS-X4418-GB Oversubsc ribed ports (3–18) On
WS-X4412-2GB-TX Upli nk p orts (13–14 ) Off
WS-X4412-2GB-TX Ove rsubscribed port s (1–12) On
WS-X4416-2GB-TX Upli nk p orts (17–18 ) Off