Cisco Catalyst 3750 - MDIX Auto

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Catalyst 3750 Switch Command Reference
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Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
mdix auto
mdix auto
Use the mdix auto interface configuration command to enable the automatic medium-dependent
interface crossover (auto-MDIX) feature on the interface. When auto-MDIX is enabled, the interface
automatically detects the required cable connection type (straight-through or crossover) and configures
the connection appropriately. Use the no form of this command to disable auto-MDIX.
mdix auto
no mdix auto
Syntax Description This command has no arguments or keywords.
Defaults Auto-MDIX is enabled.
Command Modes Interface configuration
Command History
Usage Guidelines When you enable auto-MDIX on an interface, you must also set the interface speed and duplex to auto
so that the feature operates correctly.
When auto-MDIX (and autonegotiation of speed and duplex) is enabled on one or both of connected
interfaces, link up occurs, even if the cable type (straight-through or crossover) is incorrect.
Auto-MDIX is supported on all 10/100 and 10/100/1000 Mb/s interfaces and on 10/100/1000BASE-TX
small form-factor pluggable (SFP) module interfaces. It is not supported on 1000BASE-SX or -LX SFP
module interfaces.
Examples This example shows how to enable auto-MDIX on a port:
Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# speed auto
Switch(config-if)# duplex auto
Switch(config-if)# mdix auto
Switch(config-if)# end
You can verify the operational state of auto-MDIX on the interface by entering the show controllers
ethernet-controller interface-id phy privileged EXEC command.
Release Modification
12.1(14)EA1 This command was introduced.
12.2(18)SE The default setting changed from disabled to enabled.