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Commands using dd from sorted by
Terminal - Commands using dd - 142 results
dd if=/dev/cdrom of=whatever.iso
2009-09-05 09:19:41
User: 0disse0
Functions: dd
Tags: backup dd iso dvd
8
Up
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How to copy CD/DVD into hard disk (.iso)

A dear friend of mine asked me how do I copy a DVD to your hard drive? If you want to make a copy of the ISO image that was burned to a CD or DVD, insert that medium into your CD/DVD drive and (assuming /dev/cdrom is associated with your computer?s CD drive) type the following command

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo dd if=/dev/hda1 of=/dev/hdb2
2009-09-05 09:16:52
User: 0disse0
Functions: dd sudo
Tags: backup dd hard disk
5
Up
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Clone IDE Hard Disk

This command clone the first partition of the primary master IDE drive to the second partition

of the primary slave IDE drive (!!! back up all data before trying anything like this !!!)

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo capitalize | { dd bs=1 count=1 conv=ucase 2> /dev/null; cat ;}
2009-09-05 01:49:53
User: twfcc
Functions: cat dd echo
-1
Up
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Capitalize the word with dd
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd bs=1 seek=2TB if=/dev/null of=ext3.test
2009-09-03 08:35:20
User: Superhuman
Functions: dd
5
Up
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Create a large test file (taking no space).
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dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
2009-08-07 06:32:55
User: amaymon
Functions: cut dd sed tr
Tags: dd sed cut tr
0
Up
Down
Generate Random Passwords
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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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 | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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 "[^ ]")
2009-07-22 03:59:07
User: friedchuckles
Functions: dd echo grep read sleep tr true
Tags: color
2
Up
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Matrix Style

Same as above but slooooow it down

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time dd if=/dev/zero of=blah.out oflag=direct bs=256M count=1
2009-07-15 07:17:32
User: olorin
Functions: dd time
0
Up
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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).

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dd if=/dev/zero bs=256M count=1 | nc [remoteIP] [remotePort] and on the other host nc -l port >/dev/null
2009-07-14 20:30:52
User: tkunz
Functions: dd host
Tags: network performance
0
Up
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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.

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time (dd if=/dev/zero of=blah.out bs=256M count=1 ; sync )
2009-07-14 20:19:23
User: tkunz
Functions: dd sync time
2
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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.

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# 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
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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)

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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
Down
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
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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
Up
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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
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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
Down
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.

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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

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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

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dd if=/dev/urandom of=file.img bs=4KB& pid=$!
2009-04-08 05:56:47
User: atoponce
Functions: dd
8
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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.

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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
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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
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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

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