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Commands tagged dd from sorted by
Terminal - Commands tagged dd - 60 results
od -vt x1 /tmp/spaghettifile
dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
no_of_files=10; counter=1; while [[ $counter -le $no_of_files ]]; do echo Creating file no $counter; dd bs=1024 count=$RANDOM skip=$RANDOM if=/dev/sda of=random-file.$counter; let "counter += 1"; done
2009-07-31 16:34:47
User: rajaseelan
Functions: dd echo file
Tags: bash dd
0

Create a bunch of random files with random binary content. Basically dd dumps randomly from your hard disk to files random-file*.

# dd if=/dev/sda | gzip -c | ssh user@ip 'dd of=/mnt/backups/sda.dd'
dd if=/dev/zero of=testfile.txt bs=1M count=10
2009-06-17 17:06:16
User: mstoecker
Functions: dd
Tags: dd size test file
1

This will create a 10 MB file named testfile.txt. Change the count parameter to change the size of the file.

As one commenter pointed out, yes /dev/random can be used, but the content doesn't matter if you just need a file of a specific size for testing purposes, which is why I used /dev/zero. The file size is what matters, not the content. It's 10 MB either way. "Random" just referred to "any file - content not specific"

dd if=/dev/zero of=/dev/sdb bs=446 count=1
2009-06-07 10:29:49
User: dcabanis
Functions: dd
Tags: dd grub boot usb
0

If you don't want your computer to try to boot form a USB stick that used to be used as a boot device (maybe for a live linux distro), you will have to remove the boot loader from your stick other wise the boot will fail each time the device is attached to your PC.

sudo dd if=/dev/zero of=/swapfile bs=1024 count=1024000;sudo mkswap /swapfile; sudo swapon /swapfile
2009-05-27 21:10:50
User: dcabanis
Functions: dd mkswap sudo swapon
18

Create a temporary file that acts as swap space. In this example it's a 1GB file at the root of the file system. This additional capacity is added to the existing swap space.

echo -n $HEXBYTES | xxd -r -p | dd of=$FILE seek=$((0x$OFFSET)) bs=1 conv=notrunc
2009-03-11 17:02:24
User: zombiedeity
Functions: dd echo
2

Replace (as opposed to insert) hex opcodes, data, breakpoints, etc. without opening a hex editor.

HEXBYTES contains the hex you want to inject in ascii form (e.g. 31c0)

OFFSET is the hex offset (e.g. 49cf) into the binary FILE

killall -USR1 dd
2009-03-04 08:30:20
User: vint
Functions: killall
Tags: dd
7

if you need see progress of long dd command, enter subj on other console

sudo dd if=/dev/sda of=/media/disk/backup/sda.backup
2009-02-27 20:23:37
User: bandit36
Functions: dd sudo
Tags: backup dd
13

This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations.

sudo dd if=/media/disk/backup/sda.backup of=/dev/sda

Alternatively, you can use an SSH connection to do your backups:

dd if=/dev/sda | ssh user@ssh.server.com dd of=~/backup/sda.backup