NIC Diagnostics

ethtool (Linux)

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/sbin/mii-tool (Linux)

Check/set 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.

mii-diag.c (Linux)

Check/set the status of a network interface's Media Independent Inter­face (MII) unit. [/home/isd/public_html/_utils_goodies/_src/mii-diag.c] Even works on RedHat 6.2.

/usr/sbin/ndd (Solaris)

Get and set driver configuration parameters.