for i in /sys/class/net/*; do e=`basename $i`; echo "# $e"; sudo ethtool $e | grep -E "Link|Speed" ; done

Get a summary of network devices in the system

Basically an improvement on an earlier ethtool command line.
Sample Output
# eth0
	Speed: Unknown! (65535)
	Link detected: no
# eth1
	Speed: 100Mb/s
	Link detected: yes
# lo
	Link detected: yes
# pan0
	Link detected: yes
# tap1
	Speed: 10Mb/s
	Link detected: no

By: hank
2009-04-25 14:32:08

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What Others Think

Again, your way of using "ls" inside a for loop is inappropriate. Just don't. for i in /sys/class/net/*; do ...
ubersoldat · 473 weeks and 4 days ago
give the guy some credit. this is still awesome.
linuxrawkstar · 473 weeks and 3 days ago
So let's make things straight. This is the corrected line: for i in `ls --color=none /sys/class/net/*`; do echo "# $i"; sudo ethtool $i | grep -E "Link|Speed" ; done
dotanmazor · 473 weeks and 1 day ago
What? This can't work like that. It will pass the whole path to ethtool and fail. You should have the command cd into /sys/class/net before doing an ls, a such: for i in `cd /sys/class/net ; ls -d *`; do ...
tduvally · 351 weeks and 6 days ago
Just fixed it - thanks for the suggestions.
hank · 351 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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