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Commands using dd

Commands using dd from sorted by
Terminal - Commands using dd - 132 results
# dd if=/dev/sda | gzip -c | ssh user@ip 'dd of=/mnt/backups/sda.dd'
2009-07-06 19:05:55
User: coolman
Functions: dd gzip ssh
Tags: ssh dd gzip
1
Up
Down
clone a hard drive to a remote directory via ssh tunnel, and compressing the image
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
LC_ALL=C tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
2009-07-02 07:10:33
User: zzambia
Functions: dd grep tr
Tags: color
6
Up
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Matrix Style

Solves "tr" issues with non C-locales under BSD-like systems (like OS X)

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
2009-06-30 17:23:49
User: allinurl
Functions: dd grep tr
Tags: color
60
Up
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Matrix Style
Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
# cd $partition; dd if=/dev/zero of=ShredUnusedBlocks bs=512M; shred -vzu ShredUnusedBlocks
2009-06-21 14:17:22
User: mpb
Functions: cd dd shred
8
Up
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securely erase unused blocks in a partition

This command securely erases all the unused blocks on a partition.

The unused blocks are the "free space" on the partition.

Some of these blocks will contain data from previously deleted files.

You might want to use this if you are given access to an old computer and you do not know its provenance.

The command could be used while booted from a LiveCD to clear freespace space on old HD.

On modern Linux LiveCDs, the "ntfs-3g" system provides ReadWrite access to NTFS partitions thus enabling this method to also be used on Wind'ohs drives.

NB depending on the size of the partition, this command could take a while to complete.

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Create a random file of a specific size

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"

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
stty cbreak -echo; KEY=$(dd bs=1 count=1 2>/dev/null); stty -cbreak echo
2009-06-09 13:15:49
User: inof
Functions: dd stty
5
Up
Down
Read a keypress without echoing it

This shell snippet reads a single keypress from stdin and stores it in the $KEY variable.

You do NOT have to press the enter key!

The key is NOT echoed to stdout!

This is useful for implementing simple text menus in scripts and similar things.

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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Remove the boot loader from a usb stick

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.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/sda5 bs=2048 conv=noerror,sync | gzip -fc | lftp -u user,passwd domain.tld -e "put /dev/stdin -o backup-$(date +%Y%m%d%H%M).gz; quit"
2009-05-29 21:56:32
User: sputnick
Functions: dd gzip lftp
6
Up
Down
Backup sda5 partition to ftp ( using pipes and gziped backup )
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: Filesystem dd swapoff swapon
18
Up
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create an emergency swapfile when the existing swap space is getting tight

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.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/mem of=file.dump bs=1024 skip=0 count=1
2009-05-11 00:19:50
User: professoralex
Functions: dd
1
Up
Down
dump 1KB of data from ram to file
Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
Boot up destination machine with Knoppix live CD and run nc -l -p 9000 | dd of=/dev/sda Then on the master dd if=/dev/sda | nc <dest-ip> 9000 You can monitor bandwidth usage to see progress: nload eth0 -u M
2009-05-07 05:26:58
User: lv4tech
Functions: dd
-1
Up
Down
Cloning hard disks over the network:

This is a bit to bit copy so if you have a 500GB hard disk it will take a long time even if have Gigabit Ethernet

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=yourimage.img of=/dev/sdb1
2009-04-17 23:55:13
User: rissajeanne
Functions: dd
-9
Up
Down
Burn an image to a USB stick

where /dev/sdb1 is the name of your usb device

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/urandom of=file.img bs=4KB& pid=$!
2009-04-08 05:56:47
User: atoponce
Functions: dd
9
Up
Down
Watch the progress of 'dd'

Running this code will execute dd in the background, and you'll grab the process ID with '$!' and assign it to the 'pid' variable. Now, you can watch the progress with the following:

while true; do kill -USR1 $pid && sleep 1 && clear; done

The important thing to grasp here isn't the filename or location of your input or output, or even the block size for that matter, but the fact that you can keep an eye on 'dd' as it's running to see where you are at during its execution.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ssh user@host "cd targetdir; tar cfp - *" | dd of=file.tar
2009-03-18 07:43:22
User: bwoodacre
Functions: dd ssh
6
Up
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Transfer large files/directories with no overhead over the network

This invokes tar on the remote machine and pipes the resulting tarfile over the network using ssh and is saved on the local machine. This is useful for making a one-off backup of a directory tree with zero storage overhead on the source. Variations on this include using compression on the source by using 'tar cfvp' or compression at the destination via

ssh user@host "cd dir; tar cfp - *" | gzip - > file.tar.gz
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: bash dd binary hex edit xxd
2
Up
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Binary injection

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/cdrom | pv -s 700m | md5sum | tee test.md5
2009-03-09 00:11:42
User: asmoore82
Functions: dd md5sum tee
9
Up
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[re]verify a disc with very friendly output

[re]verify those burned CD's early and often - better safe than sorry -

at a bare minimum you need the good old `dd` and `md5sum` commands,

but why not throw in a super "user-friendly" progress gauge with the `pv` command -

adjust the ``-s'' "size" argument to your needs - 700 MB in this case,

and capture that checksum in a "test.md5" file with `tee` - just in-case for near-future reference.

*uber-bonus* ability - positively identify those unlabeled mystery discs -

for extra credit, what disc was used for this sample output?

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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Backup your hard drive with dd

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
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=10gb of=/dev/zero bs=1M count=10240
2009-02-18 15:30:29
User: logik
Functions: dd
-1
Up
Down
HDD Performance Read Test

Test your XFS filesystem and Raptor hard drives for write performance.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/zero of=10gb bs=1M count=10240
2009-02-18 15:29:38
User: logik
Functions: dd
1
Up
Down
HDD Performance Write Test

Test your XFS filesystem and Raptor hard drives for write performance.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/urandom bs=1 count=32 2>/dev/null | base64 -w 0 | rev | cut -b 2- | rev
2009-02-17 23:36:24
User: TyIzaeL
Functions: cut dd rev
1
Up
Down
Generate a Random Password

I know there are a lot of random password generators out there, but I wanted something that put out something besides hex. Set count equal to the number of bytes you want.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/random of=bigfile bs=1024 count=102400
2009-02-17 05:41:20
User: amiga500
Functions: dd
2
Up
Down
Create a 100MB file for testing transfer speed
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/zero of=/swapfile bs=1M count=64; chmod 600 /swapfile; mkswap /swapfile; swapon /swapfile
2009-02-16 18:36:38
User: starchox
Functions: chmod dd mkswap swapon
8
Up
Down
Add temporary swap space

In addition to a swap partition, Linux can also use a swap file. Some programs, like g++, can use huge amounts of virtual memory, requiring the temporary creation of extra space.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/zero of=/dev/null bs=1M count=32768
2009-02-16 12:22:18
User: jacquesloonen
Functions: dd
39
Up
Down
Processor / memory bandwidthd? in GB/s

Read 32GB zero's and throw them away.

How fast is your system?

Show sample output | Comments (14) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd bs=1 count=32 if=/dev/random 2> /dev/null | md5 | grep -o '\w*'
2009-02-15 23:22:46
User: neW1
Functions: dd grep
-5
Up
Down
Generate random password
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if="\\?\Device\CdRom0" of=c:\temp\disc1.iso bs=1M --progress
2009-02-13 16:14:50
User: piyo
Functions: dd
-1
Up
Down
Rip an ISO from a CD/DVD using the freeware dd for Windows

dd for windows is available from http://www.chrysocome.net/dd

Tested with CD-ROMs like Linux install discs

I don't know about DVD-ROMs.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate