dd is a common Unix program whose primary purpose is the low-level copying and conversion of raw data.

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294
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15answers
328k views

How do you monitor the progress of dd?

dd is a wonder allowing you to duplicate a hard drive to another, completely zero a hard drive, etc. But once you launch a dd command, there's nothing to tell you of it's progress. It just sits there ...
64
votes
6answers
66k views

Mount single partition from image of entire disk (device)

I made an image of my entire disk with dd if=/dev/sda of=/media/external_media/sda.img Now the problem is I'd like to mount an ext4 filesystem that was on that disk but mount -t ext4 -o loop /media/...
45
votes
5answers
7k views

What does the command name “dd” stand for?

I'm using dd to copy an image onto a USB. But what does dd stand for? I understand its use, but not what the name dd actually means, or is an acronym for. It doesn't even say in the man page.
37
votes
1answer
42k views

What's the difference between ddrescue, gddrescue, and dd_rescue?

The dd command is commonly used to make image backups of a drive or partition. However, it performs poorly if the source drive is unreliable or failing. I read that ddrescue/dd_rescue is a good tool ...
34
votes
7answers
41k views

How would I speed up a full disk dd?

I am doing a dd on two identical drives with this command: dd if=/dev/sda of=/dev/sdb bs=4096 Both hard drives are the exact same model number, and both have 1TB of storage space. /dev/sda uses a ...
24
votes
11answers
74k views

How to clone to a smaller harddisk?

How to clone a harddisk to a smaller sized one. Clonezilla is great but it doesn't support such functionality. Also dd and PartImage don't support this demand. rsync will not copy the MBR since an ...
20
votes
4answers
38k views

How can I know how long `dd` cloning will take? [duplicate]

I have to dd a couple of 1TB hard drives. They are taking several hours to clone and I was wondering if there was any way possible of knowing how fast they are going, how much they have done and how ...
16
votes
6answers
35k views

is 'dd' command taking too long?

I set up dd to clone a smaller system 40.00GB hard drive (/dev/sda) to a new bigger 111.00GB one connected via a USB reader (dev/sdb) and Its been going for two hours now. The activity meter on the ...
15
votes
4answers
2k views

Moving entire Linux installation to another drive

I have Ubuntu 14.04 with a lot of packages and work related stuff that I am very happy with it. It is installed on my main SSD drive which is a 120GB one (I had choosen "/" when I installed ubuntu, so ...
15
votes
2answers
17k views

Why dd is not a reliable command to write bootable .iso files to USB thumb drive?

As the answers here indicate Ubuntu .iso s are not expected to boot if copied with dd to a USB thumb drive. Now my question is why is so that some Linux distributions have the option to directly write ...
13
votes
1answer
740 views

Does dd act at the filesystem level or go to the raw device directly?

Does dd act at the filesystem level or go to the raw device directly?
13
votes
5answers
4k views

Is there a way to recover files from a storage device partially overwritten with dd?

I'm an idiot, I was writing an image to a USB drive using dd when instead of typing /dev/sdb I typed /dev/sdd and wrote the 135mb image to my 750gb External Hardrive full of files. Is there ANY ...
10
votes
3answers
457 views

Could it be possible to make a hot copy of a system?

I'd like to backup my system without turning it off. The system clone should also able to run in an other machine. I've tried to "dd" the entire system partition on another disk, after that I'm ...
9
votes
5answers
1k views

What happens when I use 'dd' to overwrite the disk from which Ubuntu is running?

What would happen if I use sudo dd if=/dev/zero of=/dev/sda from an Ubuntu install running from /dev/sda? I tried it in a VM, and it appears to correctly have wiped the disk. Will this be the ...
8
votes
4answers
18k views

Mount sd-card image (created using dd)

I have created an image of my Raspberry Pi SD-card using dd: sudo dd if=/dev/sdf of=/home/myusername/raspberry-backup-2014-04-10.img The SD-card includes two partitions (one vfat, one ext4) which ...
8
votes
2answers
9k views

Is my command to clone a drive optimal?

I have done half an hour reading around to prepare to clone my hard drive. It has multiple partitions, including a Windows partition. I am going to buy a very large external hard drive for the ...
7
votes
4answers
1k views

Format usb and confirm all zeros

I want to format my usb drive and confirm that it has been filled with all zeros. For formatting this is the command I am using: sudo mkfs.vfat -I /dev/sdb How do I confirm the device is filled with ...
7
votes
4answers
2k views

Drive reporting incorrect free space

So I swapped my shiny SATA SSD for an even shinier PCI-E SSD. I run my core OS on the SSD because it's silly-fast. I did this on my old SSD so I created a new EXT4 partition and then just dded the ...
6
votes
1answer
42k views

How do I use dd to clone an external USB drive installation to a local hard disk?

can I use the dd command to clone my ubuntu installation from my external disk to my local hard drive. will it even boot? I think I can, but not sure. do I need to make the output partition on my ...
6
votes
1answer
10k views

How to create a complete recovery Image for my new netbook

I just got a new acer netbook, it comes with windows 7. I wanted to know how I could create a recovery image using tools like dd. I want to know what command creates the exact backup of the hard disk ...
6
votes
2answers
908 views

Burned CD-R are not identical to the input iso image, why?

I have the issue that sometimes when I burn an iso image to a CD-R with: sudo wodim -v driveropts=burnfree -data dev=/dev/scd0 input.iso And then read it back out again with: sudo dd if=/dev/cdrom ...
5
votes
4answers
16k views

Possibility of recovering files from a dd zero-filled hard disk

I have "zero filled" (complete wiped) an external hard disk using dd, and from what I have heard: people said you should at least "zero fill" 3 times to be sure that the data are really wiped and no ...
5
votes
1answer
3k views

Copying root partition and /home to a new larger hard drive

I am getting a larger hard drive and would like to copy root directory to it. The partition for root is 20G. I would like to make it larger on the new drive. I also would like to copy /home to a ...
4
votes
6answers
899 views

Create Random non words [closed]

dd if=/dev/urandom of=a.log bs=1M count=2 Question: if this code ^ gives me random numbers, how can I get random non-words (unintelligible) such as “hgcqw”. Question 2: Can the shuf command be ...
4
votes
3answers
342 views

Corrupt pendrive after making live Ubuntu installer

I have sandisk 8GB I had kali linux installed. I tried to create Bootable live Ubuntu pendrive. I went to the terminal and issued the following commands: sudo dd if=/dev/zero of=/dev/sdb bs=1k ...
4
votes
4answers
12k views

Creating a large size file in less time

I want to create a large file ~10G filled with zeros and random values. I have tried using: dd if=/dev/urandom of=10Gfile bs=5G count=10 It creates a file of about 2Gb and exits with a exit status '...
4
votes
2answers
35k views

How do I fix an Input/Output error using dd?

Hi i'm Trying fixing my Windows 7 system with a broken harddrive, but it's still running. I'm trying copy all data to a new drive to reinstall Windows 7. Drive called SQSERVICE. I can't copy at all -...
4
votes
1answer
10k views

When cloning ext4 partition with the “dd” command to a bigger partition free space doesn't increase [duplicate]

Possible Duplicate: Drive reporting incorrect free space Recently I've been trying to clone my hd using dd tool. Everything was ok, as cloning ntfs partitions but when it comes to ext4 - dd ...
4
votes
3answers
4k views

How to recover data from a failing hard drive?

An external 3½" HDD seems to be in danger of failing — it's making ticking sounds when idle. I've acquired a replacement drive, and want to know the best strategy to get the data off of the dubious ...
4
votes
2answers
2k views

Permission denied using dd to clone main drive

So I'm trying to clone the setup of one computer to 4 identical machines on the same network. I don't fancy the idea of meddling with the insides of the computer, so I'm following the method outlined ...
4
votes
2answers
1k views

GPT PMBR size mismatch after dd clone

I am migrating my Ubuntu EFI boot system to a larger hdd. I used the command dd if=/dev/sdb of=/dev/sda I did not dismount the inputfile before copying and the outputfile was fresh unpartitioned ...
4
votes
1answer
299 views

How do i avoid starting dd over again after a system freeze?

Some days ago I decided to wipe my 750 GB hard disk in order to sell it, so I booted Ubuntu off a live DVD and started the process with sudo dd if=/dev/zero of=/dev/sda. I left dd running during the ...
3
votes
3answers
271 views

Syncing dm-crypted drives?

I have 2 usb sticks, 8GB each: usb1 = /dev/sdb usb2 = /dev/sdc usb1 is a full dm-crypted drive and I am currently using usb2 as a backup, just incase usb1 fails. I am cloning usb1 to usb2 using ...
3
votes
2answers
1k views

How do I do a raw write to a cd with dd?

How do I do a raw write to my CD drive /dev/scd0? I want to write a bootloader (that takes two sectors) directly onto a CD, is this possible?
3
votes
1answer
3k views

How to recover from wiping by dd a partition table on external disk?

Yesterday I used dd to write an OS into my Raspberry Pi flash card. Even though all my commands ( I checked history ) were for /dev/sdd which was the flash , when I checked my external drive(500GB) ...
3
votes
3answers
4k views

Why can't Mint boot my cloned Ubuntu partition? (UUID issue)

I've been running Ubuntu 10.04 and just installed Linux Mint 13. I may go with Linux Mint full-time, but for now I wanted to install it to the first partition, but keep Ubuntu bootable. Device ...
3
votes
3answers
2k views

How to make a USB drive bootable after live image is copied into it using `dd` command?

I was unable to create live USB drive using dd command while unetbootin works. The former method used to work fine on the particular USB Drive. Is the USB drive filesystem corrupted? If yes, how do I ...
3
votes
1answer
327 views

How to copy directories and files from a corrupted harddrive?

I have an I/O error every time I copy folders and files from a partition to a backup harddrive . So how can I safely backup this data to my backup HDD?
3
votes
3answers
5k views

USB Disk stuck in read only after dd an ISO

This has probably been asked before but I have not been able to find it so I'll ask again. Here's what I did: sudo dd if=./windows.iso of=/dev/sdb #sdb is a 64gb USB disk Afterwards I was unable ...
3
votes
1answer
1k views

How to make DD make a copy of my iPod's harddrive into my computer?

I'm trying to do this, I'm sure you don't wanna read all that then I'll make a resume on it: A file was accidentally deleted on a iPod4, I need to recover it and I've been able to do all the process ...
3
votes
1answer
4k views

Error, even with sudo: “dd: failed to open ‘/dev/sda1’: Permission denied” (dd input piped from gzip)

My command which doesn't work: sudo gzip -dc sda1.image.gz | dd of=/dev/sda1 returns the following error even before I've had a chance to enter my password: dd: failed to open ‘/dev/sda1’: ...
3
votes
1answer
6k views

fallocate failed: Operation not supported

When running, fallocate -l 10G /path/to/file I'm returned the following error: fallocate: file: fallocate failed: Operation not supported Creating the file using dd (if=/dev/zero or if=/dev/...
3
votes
1answer
555 views

What is the best value for the bs option of dd command?

I am using the dd command for the first time, so I am wary, I've reading articles in wikipedia but have some unclear part, so I am asking here, is bs option matter? If I set the wrong number, would ...
3
votes
2answers
145 views

Used dd to backup a disk, now want to look at the filesystem

I dd copied /dev/sdd sudo dd if=/dev/sdd of=backup.img sudo fdisk backup.img Command (m for help): p Disk backup.img: 143.3 GB, 143274860544 bytes 61 heads, 35 sectors/track, 131069 cylinders, ...
3
votes
1answer
797 views

How to fix HDD after doing a dd cloning

So yesterday I received a HDD that was used for cloning, the whole thing went like this: An HDD of 1TB which had 120GB used was resized to 140GB. After that they did the following: sudo dd if=/dev/...
3
votes
4answers
4k views

Can't boot after a dd, BIOS reports no bootable drives

I bought a new computer, removed the Windows disk (as usual) and installed 2 brand new 3TB drives. Installed 11.10 from USB stick, apt-get updates and favorite installs, everything was fine. Then I ...
3
votes
3answers
67 views

how do i make shell ask for confimation for rm -rf command (even sudo)?

I want to make the command shell to prompt me for confirmation before execution of certain commands like dd , rm -rf etc.
3
votes
0answers
376 views

How to use a `dd if=/dev/sda of=/dev/sdb` drive?

Given: a sudo dd if=/dev/sda of=/dev/sdb duplicate drive of the main boot drive. How does one safely, reliably : mount a dd duplicate drive as a second drive? setup the dd duplicate drive as ...
2
votes
3answers
1k views

dd image size - does it equal the size of the partition?

I am using dd to create an image of my boot partition on Ubuntu 14.04. This is my first time doing this. In checking the usage on my disk, I used df -h. You will see that my /dev/sda1 partition is 5....
2
votes
2answers
4k views

Cloning with DD command

How can I backup a partition (not the whole disk) to another partition on an external hard-disk using DD? I achieved this with the following command: sudo dd if=/dev/sda6 of=/dev/sdb3 bs=1M ...