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 utility checks or sets the status of a network interface's Media Independent Inter-
face (MII) unit. Most fast ethernet adapters use an MII to autonegotiate link speed and
Most intelligent network devices use an autonegotiation protocol to communicate what media
technologies they support, and then select the fastest mutually supported media technol-
ogy. 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 inter-
face. If an interface or interfaces are not specified on the command line, then mii-tool
will check any available interfaces from eth0 through eth7.
Display more detailed MII status information. If used twice, also display raw MII
Display program version information.
Reset the MII to its default configuration.
Watch interface(s) and report changes in link status. The MII interfaces are
polled at one second intervals.
Used with -w, records link status changes in the system log instead of printing on
-F media, --force=media
Disable autonegotiation, and force the MII to either 100baseTx-FD, 100baseTx-HD,
10baseT-FD, or 10baseT-HD operation.
-A media,..., --advertise=media,...
Enable and restart autonegotiation, and advertise only the specified media tech-
nologies. Multiple technologies should be separated by commas. Valid media are
100baseT4, 100baseTx-FD, 100baseTx-HD, 10baseT-FD, and 10baseT-HD.
SIOCGMIIPHY on 'eth?' failed: Invalid argument
If the interface is not running (up), kernel will refuse to report its link state.
SIOCGMIIPHY on 'eth?' failed: Operation not permitted
Most kernels restrict access to root.
SIOCGMIIPHY on 'eth?' failed: No such device
This error is shown, if the kernel does not know about the named device.
SIOCGMIIPHY on 'eth?' failed: Operation not supported
The interface in question does not support MII queries. Most likely, it does not
have MII transceivers, at all.
David Hinds - firstname.lastname@example.org
Donald Becker - email@example.com
Bernd Eckenfels - firstname.lastname@example.org
net-tools 2004/03/28 23:30:00 MII-TOOL(8)