Cisco Catalyst 4500 Series - Configuring Auto-MDIX on a Port

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Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
OL-25340-01
Chapter 7 Configuring Interfaces
Configuring Optional Interface Features
Switch(config)# interface tenGigabitEthernet 2/1
Switch(config-if)# link debounce
Warning: Enabling debounce feature causes link down detection to be delayed
Switch(config-if)# exit
This example shows how to enable the port debounce timer of 5000 ms on 10-Gigabit Ethernet port 2/2
and to verify the setting:
Switch# config terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface tenGigabitEthernet 2/2
Switch(config-if)# link debounce time 5000
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 10
Te2/2 enable 5000
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.
Note The following line cards do not support Auto-MDIX, neither by default nor by CLI:
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.
Note The following line cards support Auto-MDIX through the CLI on their copper media ports:
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 7-3 shows the link states that results from auto-MDIX settings and correct and incorrect cabling.