Ubuntu Manpage: mii-tool - view, manipulate media-independent interface status

Provided by: net-tools_1.60+git20180626.aebd88e-1ubuntu1_amd64

NAME

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

SYNOPSIS

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

DESCRIPTION

       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.

OPTIONS

-v, --verbose
Display more detailed MII status information. If used twice, also display raw MII
register contents.
Alert: If used three times, will force reading all MII registers, including non
standard ones. It's not guaranteed any valid answer from PHY while PHY
communication can even hang. With driver e1000e will fail while reading register
0x07.

-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 100baseTx-FD, 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.

-p addr, --phy=addr
Override the MII address provided by kernel with value addr.

DIAGNOSTICS

       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.

AUTHORS