> Linux Man Page: "mii-tool"


Search with Google


The Linux Documentation Project maintains an archive of snaphots of the (English language) core Linux manual pages that are maintained by Michael Kerrisk. Corrections and additions are welcome, but review the "Help Wanted" list, first.

Man pages belonging to programs are usually distributed together with those programs. Therefore, the core Linux man-pages mainly contains the pages for system calls and library routines, special devices, and file formats. However, it also contains documentation for a few programs, in cases where the authors or maintainers of the program do not distribute man pages themselves.

This page is part of release 3.11 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at


man page(1) manual page Table of Contents


mii-tool - view, manipulate media-independent interface status


mii-tool [-v, --verbose] [-V, --version] [-R, --reset] [-r, --restart] [-w, --watch] [-l, --log] [-A, --advertise=media,...] [-F, --force=media] [interface ...]


This program is obsolete. Valid media are only 100baseT4, 100baseTxFD,100baseTx-HD, 10baseT-FD and 10baseT-HD ethernet cards. For replacement check ethtool.


This utility checks or sets the status of a network interface’s Media Independent Interface (MII) unit. Most fast ethernet adapters use an MII to autonegotiate link speed and duplex setting.

Most intelligent network devices use an autonegotiation protocol to communicate what media technologies they support, and then select the fastest mutually supported media technology. The -A or --advertise options can be used to tell the MII to only advertise a subset of its capabilities. Some passive devices, such as single-speed hubs, are unable to autonegotiate. To handle such devices, the MII protocol also allows for establishing a link by simply detecting either a 10baseT or 100baseT link beat. The -F or --force options can be used to force the MII to operate in one mode, instead of autonegotiating. The -A and -F options are mutually exclusive.

The default short output reports the negotiated link speed and link status for each interface. If an interface or interfaces are not specified on the command line, then mii-tool will check any available interfaces from eth0 through eth7.


-v, --verbose
Display more detailed MII status information. If used twice, also display raw MII register contents.

-V, --version
Display program version information.

-R, --reset
Reset the MII to its default configuration.

-r, --restart
Restart autonegotiation.

-w, --watch
Watch interface(s) and report changes in link status. The MII interfaces are polled at one second intervals.

-l, --log
Used with -w, records link status changes in the system log instead of printing on standard output.

-F media, --force=media
Disable autonegotiation, and force the MII to either 100baseTxFD, 100baseTx-HD, 10baseT-FD, or 10baseT-HD operation.

-A media,..., --advertise=media,...
Enable and restart autonegotiation, and advertise only the specified media technologies. Multiple technologies should be separated by commas. Valid media are 100baseT4, 100baseTx-FD, 100baseTx-HD, 10baseT-FD, and 10baseT-HD.

See Also



David Hinds - Donald Becker -

Table of Contents

use open software!