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Fill a hard drive with ones - like zero-fill, but the opposite :)

Terminal - Fill a hard drive with ones - like zero-fill, but the opposite :)
perl -e '$s="$s\xFF" while length($s)<512; print $s while 1' | dd of=/dev/sdX
2012-08-20 05:33:28
User: stonefoz
Functions: dd perl
0
Fill a hard drive with ones - like zero-fill, but the opposite :)

Alternatives

There are 8 alternatives - vote for the best!

Terminal - Alternatives
tr '\000' '\377' < /dev/zero | dd bs=512 count=200000 status=noxfer | pipebench | sudo dd of=/dev/sdx
2010-08-31 15:38:27
User: Gliktch
Functions: dd sudo tr
3

Note: Replace 200000 with drive bytes/512, and /dev/sdx with the destination drive/partition. ;)

Note: You may need to install pipebench, this is easy with "sudo apt-get install pipebench" on Ubuntu.

The reason I hunted around for the pieces to make up this command is that I wanted to specifically flip all of the bits on a new HDD, before running an Extended SMART Self-Test (actually, the second pass, as I've already done one while factory-zeroed) to ensure there are no physical faults waiting to compromise my valuable data. There were several sites that came up in a Google search which had a zero-fill command with progress indicator, and one or two with a fill-with-ones command, but none that I could find with these two things combined (I had to shuffle around the dd command(s) to get this to happen without wasting speed on an md5sum as well).

For reference, these are the other useful-looking commands I found in my search:

Zero-fill drive "/dev/sdx", with progress indicator and md5 verification (run sudo fdisk -l to get total disk bytes, then divide by 512 and enter the resulting value into this command for a full wipe)

dd if=/dev/zero bs=512 count=<size/512> | pipebench | sudo tee /dev/sdx | md5sum

And this command for creating a file filled with ones is my other main source (besides the above command and man pages, that is - I may be a Linux newbie but I do read!):

tr '\000' '\377' < /dev/zero | dd of=allones bs=1024 count=2k

Hope someone finds this useful! :)

Cheers,

- Gliktch

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