1MII-DIAG(8) System Manager's Manual MII-DIAG(8)
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6 mii-diag - Network adapter control and monitoring
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9 mii-diag [options]<interface>
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12 This manual page documents briefly the mii-diag network adapter control
13 and monitoring command. Addition documentation is available from
14 http://scyld.com/diag/index.html.
15 This mii-diag command configures, controls and monitors the transceiver
18 management registers for network interfaces, and configures driver
19 operational parameters. For transceiver control mii-diag uses the
20 Media Independent Interface (MII) standard (thus the command name). It
21 also has additional Linux-specific controls to communicate parameters
22 such as message enable settings and buffer sizes to the underlying
23 device driver.
24 The MII standard defines registers that control and report network
26 transceiver capabilities, link settings and errors. Examples are link
27 speed, duplex, capabilities advertised to the link partner, status LED
28 indications and link error counters.
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32 The mii-diag command supports both single character and long option
33 names. Short options use a single dash (´-´) in front of the option
34 character. For options without parameters, multiple options may be
35 concatenated after a single dash. Long options are prefixed by two
36 dashes (´--´), and may be abbreviated with a unique prefix. A long
37 option may take a parameter of the form --arg=param or --arg param.
38 A summary of options is as follows.
41 -A, --advertise <speed|setting>
44 -F, --fixed-speed <speed|setting>
45 Speed is one of: 100baseT4, 100baseTx, 100baseTx-FD, 100baseTx-
47 HD, 10baseT, 10baseT-FD, 10baseT-HD. For more precise control
48 an explict numeric register setting is also allowed.
49 -a, --all-interfaces
53 Show the status of all interfaces. This option is not recom‐
54 mended with any other option, especially ones that change set‐
55 tings.
56 -s,--status
59 Return exit status 2 if there is no link beat.
60 -D Increase the debugging level. This may be used to understand
63 the actions the command is taking.
64 -g, --read-parameters
67 Show driver-specific parameters.
68 -G, --set-parameters value[,value...]
71 Set driver-specific parameters. Set a adapter-specific parame‐
72 ters. Parameters are comma separated, with missing elements
73 retaining the existing value.
74 -v Increase the verbosity level. Additional "-v" options increase
77 the level further.
78 -V Show the program version information.
81 -w, --watch
84 Continuously monitor the transceiver and report changes.
85 -? Emit usage information.
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91 Calling the command with just the interface name (which defaults to
92 capabilities, configuration and current status.
93 The '--monitor' option allows scripting link beat changes.
96 This option is similar to --watch, but with lower overhead and sim‐
98 plifed output. It polls the interface only once a second and the out‐
99 put format is a single line per link change with three fixed words
100 <unknown|down||negotiating|up> <STATUS> <PARTNER-CAP>
101 Example output: mii-diag --monitor eth0
103 down 0x7809 0x0000
104 negotiating 0x7829 0x45e1
105 up 0x782d 0x45e1
106 down 0x7809 0x0000
107 This may be used as
110 mii-diag --monitor eth0 |
111 while read linkstatus bmsr linkpar; do
112 case $linkstatus in
113 up) ifup eth0 ;;
114 down) ifdown eth0 ;;
115 esac
116 done
117 It may be useful to shorten the DHCP client daemon timeout if it does
120 not receive an address by adding the following setting to /etc/syscon‐
121 fig/network: DHCPCDARGS="-t 3"
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125 ether-wake(8),net-diag(8),mii-tool(8).
126 Addition documentation is available from
127 http://scyld.com/diag/index.html.
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131 The --all-interfaces option is quirky. There are very few settings
132 that are usefully applied to all interfaces.
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136 The manual pages, diagnostic commands, and many of the underlying Linux
137 network drivers were written by Donald Becker for the Scyld Beowulf(™)
138 cluster system.
139Scyld Beowulf September 9, 2003 MII-DIAG(8)