Configuring Auto-Mdix On A Port - Cisco Catalyst 4500 Series Software Configuration Manual

Warning: Enabling debounce feature causes link down detection to be delayed
Switch(config-if)# end
Switch#
Switch# show interfaces debounce | include enable
Te2/1 enable
Te2/2 enable
Switch#

Configuring Auto-MDIX on a Port

When automatic medium-dependent-interface crossover (auto-MDIX) is enabled on an port, the port automatically detects the
required cable connection type (straight through or crossover) and configures the connection appropriately. When connecting
switches without the auto-MDIX feature, you must use straight-through cables to connect to devices such as servers,
workstations, or routers and crossover cables to connect to other switches or repeaters. With auto-MDIX enabled, use either
type of cable to connect to other devices; the interface automatically corrects for any incorrect cabling. For more information
about cabling requirements, see the hardware installation guide.
Auto-MDIX is enabled by default. When you enable auto-MDIX, you must also set the speed on the port to auto so that for
the feature to operate correctly. auto-MDIX is supported on copper media ports. It is not supported on fiber media ports.
Note The following line cards support Auto-MDIX by default, when port auto-negotiation is enabled:
WS-X4424-GB-RJ45, WS-X4448-GB-RJ45,WS-X4548-GB-RJ45 and WS-X4412-2GB-T. You cannot
disable them with the mdix command.
The following line cards do not support Auto-MDIX, neither by default nor by CLI:
Note
WS-X4548-GB-RJ45V, WS-X4524-GB-RJ45V, WS-X4506-GB-T,WS-X4148-RJ, WS-X4248-RJ21V,
WS-X4248-RJ45V, WS-X4224-RJ45V and WS-X4232-GB-RJ.
The following line cards support Auto-MDIX through the CLI on their copper media ports:
Note
WS-X4124-RJ45, WS-X4148-RJ45 (hardware revision 3.0 or higher), and WS-X4232-GB-RJ45
(hardware revision 3.0, or higher), WS-X4920-GE-RJ45, WS-4648-RJ45V+E, WS-X4748-UPOE+E
and WS-X4748-RJ45+E (Auto-MDIX support when inline power is disabled on the port).
Table 9-7 shows the link states that results from auto-MDIX settings and correct and incorrect cabling.
Table 9-7
Local Side auto-MDIX
On
On
Off
Off
To configure auto-MDIX on a port, perform this task:
Chapter 9 Configuring Interfaces
10
5000
Link Conditions and auto-MDIX Settings
Remote Side auto-MDIX With Correct Cabling
On
Off
On
Off
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS
Configuring Optional Interface Features
With Incorrect Cabling
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