Commands using dd sorted by votes

Commands using dd (168)

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Efficient remote forensic disk acquisition gpg-crypted for multiple recipients

Acquires a bit-by-bit data image, gzip-compresses it on multiple cores (pigz) and encrypts the data for multiple recipients (gpg -e -r). It finally sends it off to a remote machine.
This is sample output - yours may be different.
3

dd if=/dev/sdb | pigz | gpg -r <recipient1> -r <recipient2> -e --homedir /home/to/.gnupg | nc remote_machine 6969

brainstorm · 2010-12-31 19:24:37 8
dd with progress bar and statistics

Uses the pv utility to show progress of data transfer and an ETA until completion. You can install pv via Homebrew on macOS Show Sample Output
This is sample output - yours may be different.
```
27.4MiB 0:00:13 [2.02MiB/s] [====>                     ]  0% ETA 0:35:13
```
3

sudo pv -tpreb /path/to/source | sudo dd bs=4096 of=/path/to/destination

thealanberman · 2017-03-01 19:11:57 18
Create a DOS floppy image

mount with: mount -t msdos -o loop ./floppy.img /tmp/mnt
This is sample output - yours may be different.
2

dd if=/dev/zero bs=1024 count=1440 > floppy.img && mkdosfs floppy.img

wwest4 · 2009-02-05 18:56:55 46
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
This is sample output - yours may be different.
2

echo -n $HEXBYTES | xxd -r -p | dd of=$FILE seek=$((0x$OFFSET)) bs=1 conv=notrunc

zombiedeity · 2009-03-11 17:02:24 360
Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible. Show Sample Output
This is sample output - yours may be different.
```
1+0 records in
1+0 records out
268435456 bytes (268 MB) copied, 1.50648 seconds, 178 MB/s

real    0m7.119s
user    0m0.002s
sys     0m0.649s
```
2

time (dd if=/dev/zero of=blah.out bs=256M count=1 ; sync )

tkunz · 2009-07-14 20:19:23 7
Matrix Style

Same as above but slooooow it down
This is sample output - yours may be different.
2

while true ; do IFS="" read i; echo "$i"; sleep .01; done < <(tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]")

friedchuckles · 2009-07-22 03:59:07 9
A DESTRUCTIVE command to render a drive unbootable

Overwrites the boot sector. Since this doesn't overwrite any data, you can usually recover by re-creating the partition table exactly the same as before you zeroed it. This can also help sometimes if you install a new drive in a Windows machine which can't read it.
This is sample output - yours may be different.
2

dd if=/dev/zero of=/dev/fd0 bs=512 count=1

andrew112358 · 2009-09-09 23:43:22 8
Restore a local drive from the image on remote host via ssh
This is sample output - yours may be different.
2

ssh user@server 'dd if=sda.img' | dd of=/dev/sda

newrain7803 · 2009-10-20 06:52:26 4
Split a file one piece at a time, when using the split command isn't an option (not enough disk space)

bs = buffer size (basically defined the size of a "unit" used by count and skip) count = the number of buffers to copy (16m * 32 = 1/2 gig) skip = (32 * 2) we are grabbing piece 3...which means 2 have already been written so skip (2 * count) i will edit this later if i can to make this all more understandable
This is sample output - yours may be different.
2

dd if=inputfile of=split3 bs=16m count=32 skip=64

jearsh · 2010-02-21 10:09:46 3
generate random mac address
This is sample output - yours may be different.
2

2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1 | sed '2d;s/^0\+ //;s/ /:/g'

jianingy · 2010-04-30 00:44:21 43
Create a file of a given size in linux

If you're trying to create a sparse file, you can use dd by 'skip'ing to the last block instance. ls -ls shows the actual size vs. the reported size Show Sample Output
This is sample output - yours may be different.
```
ubahmapk@linux:~$ dd if=/dev/zero of=sparse_file skip=1024 bs=1024 count=1
1+0 records in
1+0 records out
1024 bytes (1.0 kB) copied, 4.6444e-05 s, 22.0 MB/s
ubahmapk@linux:~$ ls -lhs sparse
4.0K -rw-r--r-- 1 ubahmapk ubahmapk 1.0K 2010-10-23 19:25 sparse_file
```
2

dd if=/dev/zero of=sparse_file bs=1024 skip=1024 count=1

ubahmapk · 2010-10-24 00:28:34 6
Set laptop display brightness

An alternative which does not require to be root
This is sample output - yours may be different.
2

echo <percentage> | sudo dd of=/proc/acpi/video/VGA/LCD/brightness

alperyilmaz · 2011-01-05 03:57:58 7
Watch the progress of 'dd'

Only slightly different than previous commands. The benefit is that your "watch" should die when the dd command has completed. (Of course this would depend on /proc being available)
This is sample output - yours may be different.
2

dd if=/dev/urandom of=file.img bs=4KB& pid=$!; while [[ -d /proc/$pid ]]; do kill -USR1 $pid && sleep 1 && clear; done

unixmonkey14934 · 2011-06-24 21:49:10 8
Extract the MBR ID of a device

Useful when you want to know the mbrid of a device - for the purpose of making it bootable. Certain hybridiso distros, for eg the OpenSUSE live ISO uses the mbrid to find the live media. Use this command to find out the mbrid of your USB drive and then edit the /grub/mbrid file to match it. Show Sample Output
This is sample output - yours may be different.
```
0x8de54e0a
```
2

dd if=/dev/sda bs=1 count=4 skip=$((0x1b8)) 2>/dev/null | hexdump -n4 -e '"0x%x\n"'

d3Xt3r · 2011-07-30 02:42:32 4
Test disk I/O

Especially useful to gauge the performance of a VPS. Show Sample Output
This is sample output - yours may be different.
```
16384+0 records in
16384+0 records out
1073741824 bytes (1.1 GB) copied, 6.10176 seconds, 176 MB/s
```
2

dd if=/dev/zero of=test bs=64k count=16k conv=fdatasync

marcel · 2011-08-14 16:37:06 4
copy hybrid iso images to USB key for booting from it, progress bar and remaining time are displayed while copying
This is sample output - yours may be different.
2

time (pv file.iso | dd bs=1M oflag=sync of=/dev/sdX 2>/dev/null)

dash · 2012-01-29 09:44:33 4
dd with progress bar and statistics to gzipped image

This is a useful command to backup an sd card with relative total size for piping to pv with a progressbar
This is sample output - yours may be different.
2

export BLOCKSIZE='sudo blockdev --getsize64 /dev/sdc' && sudo dd if=/dev/sdc bs=1MB | pv -s $BLOCKSIZE | gzip -9 > USB_SD_BACKUP.img.gz

hur1can3 · 2013-02-05 18:10:25 6
Create a random file of a certain, and display progress along the way.

SIZE is the number of gigabytes and the file name is at the end. Random data is generated by encrypting /dev/zero, similar to other techniques posted on here.
This is sample output - yours may be different.
2

SIZE=1; dd if=/dev/zero bs=1M count=$((SIZE*1024)) | pv -pters $((SIZE*1024*1024*1024)) | openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt > randomfile

kennethjor · 2014-08-30 01:46:51 8
iso to USB with dd and show progress status

need package: pv apt-get install pv get the iso size in byte with ls -l install-cd.iso /dev/sdb is your USB Device (without partitionNr.)
This is sample output - yours may be different.
2

dd if=/home/kozanoglu/Downloads/XenServer-7.2.0-install-cd.iso | pv --eta --size 721420288 --progress --bytes --rate --wait > /dev/sdb

aysadk · 2019-02-27 13:56:10 37
Adhoc tar backup

Creates a quick backup with tar to a remote host over ssh.
This is sample output - yours may be different.
1

tar -cvzf - /source/path | ssh <targethostname> -l <username> dd of=/destination/path/backupfile.tgz

smm · 2009-02-06 15:52:09 13
HDD Performance Write Test

Test your XFS filesystem and Raptor hard drives for write performance.
This is sample output - yours may be different.
1

dd if=/dev/zero of=10gb bs=1M count=10240

logik · 2009-02-18 15:29:38 1052
dump 1KB of data from ram to file

Show Sample Output
This is sample output - yours may be different.
```
1+0 records in
1+0 records out
1024 bytes (1.0 kB) copied, 0.000986997 s, 1.0 MB/s

$ file file.dump
file.dump: data

$ strings file.dump 
ReQuQ
```
1

dd if=/dev/mem of=file.dump bs=1024 skip=0 count=1

professoralex · 2009-05-11 00:19:50 4
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
This is sample output - yours may be different.
```
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.038701 s, 271 MB/s
```
1

dd if=/dev/zero of=testfile.txt bs=1M count=10

mstoecker · 2009-06-17 17:06:16 14
clone a hard drive to a remote directory via ssh tunnel, and compressing the image
This is sample output - yours may be different.
1

# dd if=/dev/sda | gzip -c | ssh user@ip 'dd of=/mnt/backups/sda.dd'

coolman · 2009-07-06 19:05:55 7
Securely destroy data on given device

Intentional hash in the beginning. May run a looong time. Wipes your data for real. Was meant to be /dev/urandom - I mistyped it. :-)
This is sample output - yours may be different.
1

# for i in $(seq 1 25); do dd if=/dev/urandom of=<your disk> bs=1M ; done

danam · 2009-09-29 07:12:34 6
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Never rewrites a file while copying (or moving)

Allows you to preserve your files when using cp, mv, ln, install or patch. When the target file exists, it will generate a file named XXX.~N~ (N is an auto-incremental number) instead of deleting the target file.

View all images

So you are in directory with loads of pictures laying around and you need to quickly scan through them all

Another Curl your IP command

Just another curl command to get your public facing IP

Kills a process that is locking a file.

Useful when you're trying to unmount a volume and other sticky situations where a rogue process is annoying the hell out of you.

Buffer in order to avoir mistakes with redirections that empty your files

A common mistake in Bash is to write command-line where there's command a reading a file and whose result is redirected to that file. It can be easily avoided because of : 1) warnings "-bash: file.txt: cannot overwrite existing file" 2) options (often "-i") that let the command directly modify the file but I like to have that small function that does the trick by waiting for the first command to end before trying to write into the file. Lots of things could probably done in a better way, if you know one...

Unlock your KDE4 session remotely (for boxes locked by KDE lock utility)

Do the unlock KDE screen saver locked session with lightdm display manager used in Kubuntu 12.10 +

Quickly build ulimit command from current values

It is helpful to know the current limits placed on your account, and using this shortcut is a quick way to figuring out which values to change for optimization or security. Alias is: $ alias ulimith="command ulimit -a|sed 's/^.*$[a-z]$)$.*$$/-\1\2/;s/^/ulimit /'|tr '\n' ' ';echo" Here's the result of this command: $ ulimit -c 0 -d unlimited -e 0 -f unlimited -i 155648 -l 32 -m unlimited -n 8192 -p 8 -q 819200 -r 0 -s 10240 -t unlimited -u unlimited -v unlimited -x unlimited $ ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 155648 max locked memory (kbytes, -l) 32 max memory size (kbytes, -m) unlimited open files (-n) 8192 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 10240 cpu time (seconds, -t) unlimited max user processes (-u) unlimited virtual memory (kbytes, -v) unlimited file locks (-x) unlimited

RTFM function

Some commands have more information on 'info' than in the man pages

convert hex to decimal ; decimal to hex

Losslessly rotate videos from your phone by 90 degrees.

Takes all the .3gp files in the directory, rotates them by 90 degrees, and saves them in the lossless ffv1 encoding. If this rotates in the wrong direction, you may want transponse=1 Re-encoding to ffv1 may result in a significant increase in file size, as it is a lossless format. Other applications may not recognize ffv1 if they don't use ffmpeg code. "huffyuv" might be another option for lossless saving of your transformations. The audio may be re-encoded as well, if the encoding used by your 3gp file doesn't work in a avi container.

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Commands using dd (168)

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