Determine Linux ethernet interface speed and duplex
Posted by Quinn McHenry in Linux networking
Determine the auto-negotiated Ethernet connection speed and duplex using the mii-tool command.
Running the following command as superuser with no options will generate basic information about all of the Ethernet interfaces on the computer:
mii-tool
The resulting output will look something like:
eth0: negotiated 100baseTx-FD, link ok
This output shows one interface (eth0) which was auto-negotiated to 100 Mbps (100baseTx) and full duplex (FD).
Adding the -v option to the command generates verbose output and will tell you more about the interface including the manufacturer and model (if available) and the interface’s capabilities.
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May 10, 2010 at 10:56 am, Anonymous said:
hi i want to find the ethernet speed and transmission details for RH Linux AS 4 system.
i have tries ethtool and mii-tool, but it does not work for RH Linux AS 4 system. please find a way to deal with it.
April 19, 2011 at 1:52 pm, Vetri said:
sudo mii-tool in the command line