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May 19, 2015 - A Look At The New Commandlinefu
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set your ssd disk as a non-rotating medium

Terminal - set your ssd disk as a non-rotating medium
sudo echo 0 > /sys/block/sdb/queue/rotational
2009-11-27 12:16:17
User: nickleus
Functions: echo sudo
set your ssd disk as a non-rotating medium

if you still get a permissions error using sudo, then nano the file:

sudo nano -w /sys/block/sdb/queue/rotational

and change 1 to 0

this thread:


says that this will "help the block layer to optimize a few decisions"


There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

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What others think

You can use sudo and tee to avoid permission errors when running a command like this:

echo 0 | sudo tee /sys/block/sdb/queue/rotational

or use sudo tee -a to append to a file.

Comment by eightmillion 347 weeks and 2 days ago

@eightmillion, thanks, i've never used tee before. now i know =) awesome.

Comment by nickleus 347 weeks and 1 day ago

The permission error occurs because the redirection is setup by your shell with your normal permissions and not by sudo. eightmillion's solution is great. Here are two more. (1) use here documents and dd:

sudo dd <<<"0" of=/sys/block/sdb/queue/rotational

(here the

sudo -e /sys/block/sdb/queue/rotational
Comment by bwoodacre 347 weeks ago

Your point of view

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