Commands using dd sorted by votes

Commands using dd (167)

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Testing hard disk writing speed
This is sample output - yours may be different.
1

time dd if=/dev/zero of=TEST bs=4k count=512000

flojb · 2009-10-17 17:50:53 39
Step#2 Create a copy of the bootload and partition table!

Step#2 Create a copy of the bootload and partition table!
This is sample output - yours may be different.
1

dd if=/dev/sda of=/home/sam/MBR.image bs=512 count=1

bbelt16ag · 2011-01-08 11:25:02 4
Remote mysql dump all databases with ssh
This is sample output - yours may be different.
1

mysqldump -u user -p --all-databases | ssh user@host dd of=/opt/all-databases.dump

ncaio · 2011-01-12 18:27:46 3
dd with progress bar and statistics

Will automatically take the size of the file but longer, usefull only if in an function.
This is sample output - yours may be different.
1

dd if=FILE | pv -s $(stat FILE | egrep -o "Size: [[:digit:]]*" | egrep -o "[[:digit:]]*") | dd of=OUTPUT

andrepuel · 2011-02-09 22:21:06 4
Watch the progress of 'dd'

The previously-posted one-liner didn't work for me for whatever reason, so I ended up doing this instead.
This is sample output - yours may be different.
1

dd if=/dev/urandom of=file.img bs=4KB& sleep 1 && pid=`pidof dd`; while [[ -d /proc/$pid ]]; do kill -USR1 $pid && sleep 10 && clear; done

unixmonkey31714 · 2012-02-23 01:45:53 3
dd with progress bar and remaining time displayed
This is sample output - yours may be different.
1

SIZE=`fdisk -s /dev/sdx`; dd if=/dev/sdx bs=1M | pv -s "$SIZE"k > hdd.img

dash · 2012-02-29 19:55:26 3
Look at your data as a greymap image.

Keep width to a power of 2 to see patterns emerge. 512 is good. So is 4096 for huge maps. PNM headers are super basic. http://netpbm.sourceforge.net/doc/pbm.html Show Sample Output
This is sample output - yours may be different.
```
Don't share this output with the Internet. It's your raw naked data.
```
1

x=1024; y=32768; cat <(echo -e "P5\n$x $y\n255\n") <(dd if=/dev/sda1 bs=$x count=$y) > sda1.pgm

adeverteuil · 2012-03-06 03:09:16 4
Create iso image of cd/dvd
This is sample output - yours may be different.
1

dd if=/dev/cdrom of=~/cdimage.iso

mesuutt · 2012-03-23 15:26:38 4
Create a file of repeated, non-zero

dd can be used with /dev/zero to easily create a file of all zero-bytes. Pipe that through tr and use octal conversions to change the byte values from zero to 0xff (octal 0377). You can replace 0377 with the byte of your choice. You can also use \\0 and \\377 instead of the quoted version.
This is sample output - yours may be different.
1

dd if=/dev/zero bs=64K count=1 | tr "\0" "\377" > all_ones

anduril462 · 2012-04-17 18:01:59 5
Test I/O performance by timing the writing of 100Mb to disk

Write 200 blocks of 512k to a dummy file with dd, timing the result. The is useful as a quick test to compare the performance of different file systems. Show Sample Output
This is sample output - yours may be different.
```
200+0 records in
200+0 records out
104857600 bytes (105 MB) copied, 19.6325 seconds, 5.3 MB/s

real    0m19.681s
user    0m0.003s
sys     0m1.427s
```
1

time dd if=/dev/zero of=dummy_file bs=512k count=200

rdc · 2012-04-20 13:47:27 4
Extract android adb ab backup to tar format (only works for non encrypted backups)
This is sample output - yours may be different.
1

dd if=mybackup.ab bs=24 skip=1 | openssl zlib -d > mybackup.tar

bugmenot · 2012-10-28 10:33:07 7
dd if=/dev/null of=/dev/sda

removes all files/filesystems of a harddisk. It removes EVERYTHING of your hard disk. Be carefull when to select a device. It does not prompt for and second check. Show Sample Output
This is sample output - yours may be different.
```
write using input file /dev/zero (all zeros)
```
1

dd if=/dev/null of=/dev/sda

metaverse · 2013-08-30 21:06:36 8
Create a PNG screenshot of Rigol Ultravision scopes attached per LAN

Scope should have the Rigol Ultravision Technology otherwise it won't accept the command. ImageMagic is required. Scope sends a 1.1M BMP file and converted to PNG it's only 18-20K
This is sample output - yours may be different.
1

echo "display:data?" | nc "$scope_ip_address" 5555 | dd bs=1 skip=11 2>/dev/null | convert bmp:- out_file.png

ichbins · 2015-06-27 06:43:43 11
iso to USB with dd and show progress status
This is sample output - yours may be different.
1

dd if=/backup/archlinux.iso of=/dev/sdb status=progress

thomasr · 2019-02-27 17:01:15 35
Generate a random password 30 characters long
This is sample output - yours may be different.
1

tr -c -d "a-zA-Z0-9" </dev/urandom | dd bs=30 count=1 2>/dev/null;echo

tlezotte · 2019-06-29 22:46:41 43
Create a hard-to-guess password

Alternatively, if your password can contain a richer character set, try using 'uuencode' rather than base64. dd if=/dev/urandom bs=16 count=1 2>/dev/null | uuencode - Sample of that: '0:.CF\-@"\`W315VG^4O\.@``' Show Sample Output
This is sample output - yours may be different.
```
a5sXvbJx0pUY/CEuxwM4YA==
```
0

dd if=/dev/urandom bs=16 count=1 2>/dev/null | base64

twopoint718 · 2009-02-05 19:19:20 16
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
This is sample output - yours may be different.
```
W9JOrpSYAwJ88z/0K1uL6z0vuZpBCgaMzD1pgILJQ5E
```
0

dd if=/dev/urandom bs=1 count=32 2>/dev/null | base64 -w 0 | rev | cut -b 2- | rev

TyIzaeL · 2009-02-17 23:36:24 12
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.
This is sample output - yours may be different.
0

dd if=/dev/zero of=/dev/sdb bs=446 count=1

dcabanis · 2009-06-07 10:29:49 7
Test network performance, copying from the mem of one box, over the net to the mem of another

Note, the [remotePort] should be opened in the firewall first. First, start the destination box listening, then fire off the sending box. Data from the /dev/zero device in memory of the source machine is read out using dd, sent over the network with nc, and read back in from the other side of the network with nc, going to the /dev/null device. Essentially, it is a memory-network-memory copy operation, the output of dd will tell you how fast your network really is performing.
This is sample output - yours may be different.
0

dd if=/dev/zero bs=256M count=1 | nc [remoteIP] [remotePort] and on the other host nc -l port >/dev/null

tkunz · 2009-07-14 20:30:52 4
Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Let dd use direct I/O to write directly to the disk without any caching. You'll encounter very different results with different block sizes (try with 1k, 4k, 1M, ... and appropriate count values).
This is sample output - yours may be different.
0

time dd if=/dev/zero of=blah.out oflag=direct bs=256M count=1

olorin · 2009-07-15 07:17:32 3
Generate Files with Random Content and Size in Bash

Create a bunch of random files with random binary content. Basically dd dumps randomly from your hard disk to files random-file*. Show Sample Output
This is sample output - yours may be different.
```
random-file.5
random-file.6
random-file.7
random-file.8
random-file.9
```
0

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

rajaseelan · 2009-07-31 16:34:47 5
Generate Random Passwords
This is sample output - yours may be different.
0

dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16

amaymon · 2009-08-07 06:32:55 5
generate random mac address

Mac OS X needs some clean up. First command works in Linux, Solaris just needs the "0000000"'s removed Show Sample Output
This is sample output - yours may be different.
```
dd:09:83:5f:9b:9d
```
0

2>/dev/null dd if=/dev/urandom bs=1 count=6 | od -t x1|sed '2d;s/0000000 *//;s/ /:/g;s/::*$//'

hckhckhck · 2010-04-30 16:57:59 3
type partial command, kill this command, check something you forgot, yank the command, resume typing.

Use this if you're using vi editing mode. Example use : sudo vim /root/bin/ ##uh... autocomplete doesn't work... dd sudo ls /root/bin ##ah! that's the name of the file! <p> sudo vim /root/bin/ ##resume here! Thanks readline!
This is sample output - yours may be different.
0

dd [...] p

bartonski · 2010-07-23 23:19:06 4
dd with progress bar and remaining time displayed
This is sample output - yours may be different.
0

SIZE=`fdisk -s /dev/sdx`; dd if=/dev/sdx bs=1M | pv -s "$SIZE"k > hdd.img

dash · 2011-06-12 20:00:26 3
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Remove all the files except abc in the directory

Finds all files in the current directory and deletes them besides file called "abc"

Transfers clipboard content from one OS X machine to another

This uses ssh to transfer the contents of one Mac's clipboard to another's. This only works with plain text, sadly. Trying to transfer images will just clear out the remote machine's clipboard, and rich text will be converted to plain text. Using the "Remote Login" must be enabled on the remote machine (via System Preferences' Sharing panel) for this to work.

SED - Substitute string in next line

source: http://sed.sourceforge.net/sed1line.txt

Remove lines that contain a specific pattern($1) from file($2).

The -i option in sed allows in-place editing of the input file. Replace myexpression with any regular expression. /expr/d syntax means if the expression matches then delete the line. You can reverse the functionality to keep matching lines only by using: $ sed -i -n '/myexpression/p' /path/to/file.txt

Look for English words in /dev/urandom

* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Sort installed rpms in alphabetic order with their size.

delay execution of a command that needs lots of memory and CPU time until the resources are available

[ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] returns true if less than 2000 MB of RAM are available, so adjust this number to your needs. [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ] returns true if the current machine load is at least equal to the number of CPUs. If either of the tests returns true we wait 10 seconds and check again. If both tests return false, i.e. 2GB are available and machine load falls below number of CPUs, we start our command and save it's output in a text file. The ( ( ... ) & ) construct lets the command run in background even if we log out. See http://www.commandlinefu.com/commands/view/3115/ .

Benchmark SQL Query

Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

Get information about memory modules

To take information about the characteristics of the installed memory modules.

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Commands using dd (167)

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