configure ports preferred-medium

configure ports port_list preferred-medium [copper | fiber] {force}


Configures the primary uplink port to use a preferred medium.

Syntax Description

port_list Specifies the port number. On a stand-alone switch, this value is just the port number, and on a SummitStack, this value is the slot and port number.
copper Specifies that the port should always use the 10/100/1000 BASE-T connection whenever a link is established even when a fiber link is also present.
fiber Specifies that the port should always use the 1 gigabit Ethernet fiber connection whenever a link is established even when a copper link is also present.
force Disables automatic failover. If the specified preferred medium is not present, the link does not come up even if the secondary medium is present.


The default is fiber.

Usage Guidelines

You specify either copper or fiber for the specified port. The switch evaluates the copper energy and the fiber signal at the time these ports come online. If both are present, the configured preferred medium is chosen; however, if only one is present, the switch brings up that medium and uses this medium the next time the switch is rebooted. When a failure occurs and the uplinks are swapped, the switch continues to keep that uplink assignment until another failure occurs or until the assignment is changed using the CLI.

If you use the force option, it disables automatic failover. If you force the preferred-medium to fiber and the fiber link goes away, the copper link is not used, even if available.

To display the preferred medium, use the show port information detail command (you must use the detail variable to display the preferred medium).

It is not recommended to use SFP in a 10G fiber combination port while designating copper forceas the preferred medium. Link does not come up if SFP is used.



Running this command on the combination ports of the ExtremeSwitching X460-G2 or the X440-G2 series switches flaps the active link once.


The following example establishes copper port 4 as the primary uplink on the ExtremeSwitching series switch and fiber port 4 as the redundant uplink port:

configure ports 4 preferred-medium copper

Copper port 4 becomes the primary uplink until a failure occurs on that link. At that time, fiber port 4 becomes the primary uplink and copper port 4 becomes the redundant port. This assignment stays in place until the next failure.


This command was first available in ExtremeXOS 11.2.

Platform Availability

This command is available on the ExtremeSwitching X460-G2, X440-G2, and X620-x series switches.