Commands using dd sorted by votes

Commands using dd (167)

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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 7
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 45
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 17:02:24 347
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 3
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 41
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 5
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 6
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 7
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 3
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 3
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 3
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 5
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 36
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 12
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 15:29:38 761
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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Remount root in read-write mode.

Saved my day, when my harddrive got stuck in read-only mode.

lotto generator

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Monitoring file handles used by a particular process

-r : repeat mode

check open ports without netstat or lsof

Join the content of a bash array with commas

This type of join is clearly documented in the bash manual. Only the first character of IFS is used for the delimiter.

Redirect a filehandle from a currently running process.

This command uses the debugger to attach to a running process, and reassign a filehandle to a file. The two commands executed in gdb are p close(1) which closes STDOUT and p creat("/tmp/filename",0600) which creates a file and opens it for output. Since file handles are assigned sequentially, this command opens the file in place of STDOUT and once the process continues, new output to STDOUT will instead be written to our capture file.

Install pip with Proxy

Installs pip packages defining a proxy

Stream system sounds over rtmp

sox (SOund eXchange) can capture the system audio be it a browser playing youtube or from hardware mic and can pipe it to ffmpeg which encodes it into flv and send it over rtmp. Tested using Red5 rtmp server.

Show GCC-generated optimization commands when using the "-march=native" or "-mtune=native" switches for compilation.

You can tell GCC to automatically select optimization commands and produce optimized code for the local machine (the one compiling the code), but you can't normally see what switches have been selected and used unless you append a "-v" and pause compilation.

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Commands using dd (167)

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