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

learn more… | top users | synonyms

0
votes
1answer
44 views

USB Flash over {H,S}DD

I have task to use 32Gb flash as place to install OS, so PC without hard drive load flash and can work(Not LiveUSB!). Of course, I can use generic install algorithm, but I have already a computer with ...
8
votes
2answers
2k views

How can I mount dd image of a partition?

I created a dd image of a partition (containing an HFS+ FS) of one of my disks (and not the entire disk) a few days ago using the following command - dd conv=sync,noerror bs=8k if=/dev/sdc2 ...
0
votes
3answers
3k views

How to mark bad-sectors on SSD drive?

My SSD drive has started to have some bad sectors. My plan is to to copy it to another drive using dd, but it seems like a few bad sectors are making this impossible. How do I mark bad sectors on ...
1
vote
3answers
2k views

Use `dd` linux program to save / recover a disk's MBR

I have an Ubuntu OS installed on my laptop. I want to install Windows 7 as well to another disk partition (I will do it by recovering it from a special partition on my laptop). After installing ...
0
votes
2answers
88 views

What happens if I write to a device other than a disk?

I know, I can write to a hard disk just using dd command in Linux, such as dd if=/dev/zero of=/dev/sdb. Since, every device is represented as file in Linux, I wonder what might happen if I ...
1
vote
4answers
1k views

bash - test if disk is unparitioned

I'm currently working on a DIY network storage which aggregates free disk space using mhddfs. Now what I want is, for example given a hotswap bay, when I insert a brand new unpartitioned disk, I wish ...
16
votes
2answers
37k views

How do I create a 1GB random file in Linux?

I am using the bash shell and would like to pipe the out of the command openssl rand -base64 1000 to the command dd such as dd if={output of openssl} of="sample.txt bs=1G count=1`. I think I can use ...
1
vote
2answers
1k views

Is it possible to mount a disk image, created with dd, to a directory on a mounted external usb hdd?

I have an image of my home (/dev/sda3) partition, which I've created using the "dd" command. dd if=/dev/sda3 of=/path/to/disk.img I've deleted the home partition via gparted in order to enlarge my ...
0
votes
2answers
66 views

dd using device label instead of device

I would like to use a device label instead of the device in a script that I am writing so I can use the script on multiple computers. I want to change the line: sudo dd if=$(TARGET) of=/dev/sdb To ...
1
vote
1answer
558 views

Cloning harddrive I/O errors after about 30 seconds

I am trying to clone a harddrive with important data to another harddrive to make sure we can keep those files safe. Now my old HD is a 500GB 3.5" and the new one is 1TB 3.5". My old HD is plugged ...
3
votes
3answers
6k views

Cloning an SD card onto a larger SD card

I'm using Ubuntu 12.04. I have an old 4GB SD card, and have just bought a new 16GB SD card. I would like to copy everything from my old 4GB SD card onto the new 16GB SD card. I was afraid that the ...
6
votes
1answer
244 views

Is it possible to 'instantly' create arbitrary files?

I've seen the following trick to create large, empty files somewhat quickly: dd if=/dev/zero of=test.dat bs=1024 count=1024 However, this still takes some time when creating multi-GB files. I ...
3
votes
1answer
607 views

dd/ddrescue style tool for SSDs that skips writes for identical blocks

I have a dd copy of a filesystem from a SSD I want to restore back to the same SSD filesystem due to a bad OS crash, putting it back into a known good state. 95% of the blocks will be the same, so to ...
7
votes
2answers
2k views

What exactly does the dd command do?

A few days ago I was delighted to find out that it's not all that difficult to write an iso image to a USB without the help of a third-party program explicitly designed to do so. But the command (or ...
0
votes
1answer
707 views

backup/image only partitioned space on sd card

i'm using dd to backup and restore sd card images but it insists on backing up the whole of the sd card including unpartitioned space. is there a way to avoid this or better process for cross platform ...
2
votes
1answer
826 views

Do you need to format a flash drive before dd an image to it?

Does dd or Windows Image Writer work regardless whether the target device was formatted or partitioned correctly? I'm trying to flash a Chromium OS build to a USB flash drive following these ...
2
votes
2answers
9k views

Making bootable USB flash drive with dd

I'm trying to make my 32GB flash drive bootable with archlinux. Beginning from release 2010.05, all ISO files can be directly written to USB media. So, what I've did: dd if=archlinux.iso of=/dev/sdc ...
5
votes
1answer
932 views

Accidentally dd'ed an image to wrong drive / overwrote partition table + NTFS partition start

I screwed up and set the wrong output for dd when trying to copy a freenas iso, overwriting the wrong external hard drive. Ironically, I was trying to setup a freenas server for data backup... ...
5
votes
1answer
393 views

File recovery: How can I make a non-destructive copy of a (NTFS) partition?

I want to recover some deleted files from a healthy NTFS partition on an undamaged hard-disk. In order to leave the partition undisturbed, i plan to use dd to clone the partition to a raw image file ...
2
votes
1answer
2k views

How to convert a specific partition in a .vdi file to .img?

VBoxManage converts the whole disk to .img. But I want to write only one partition in the vdi image to a partition on my physical disk.
1
vote
0answers
495 views

Resume interrupted multiple-file disk images created with dd?

This is the effort to recover a failed hard drive containing several important research works. To sum up: with the method I tried (described below) I could not resume failed multiple images created ...
2
votes
2answers
614 views

with a dd of an entire disk can you restore only a specific partition

I have a full dd of my hard disk which has 3 partitions, how can I using this image only restore a specific partition?
1
vote
2answers
980 views

how to prepare a harddisk for another computer

My old laptop died lately and I want to have it fixed by a repair-shop. Now first I want to clean the hard disk (via an external 2,5 inch casing). I managed to connect the drive via USB in order to ...
3
votes
1answer
216 views

Mapping dd commands to ddrescue

I'm trying to back up the Windows Recovery Partition on a laptop using ddrescue. I tried using dd, but I kept getting an Input Output error (at about 9.65 GB through, if it matters), so I learned that ...
1
vote
4answers
3k views

can dd be used to wipe clean a directory?

I have a directory on a Mint install that I want to wipe clean (not just delete the pointers, actually zero the info off the drive). is it possible to clear the data by using dd? For example, if the ...
10
votes
1answer
4k views

dd performance on Mac OS X vs. Linux

I was trying to copy an iso of the windows installer onto a hard drive to avoid burning a disk. I first tried Disk Utility's restore function, however it didn't like the ISO for some reason. Then I ...
3
votes
1answer
607 views

Migrating to LVM

The drive on my Ubuntu media server is nearly full. I hope to add another 2TB of capacity to the machine and would prefer for all 3.5 TB to be recognized as a single drive. To complicate things, I ...
5
votes
2answers
4k views

Why is GNU shred faster than dd when filling a drive with random data?

While securely erasing a hard drive before decommissioning I noticed, that dd if=/dev/urandom of=/dev/sda takes nearly a whole day, whereas shred -vf -n 1 /dev/sda only takes a couple of hours with ...
14
votes
4answers
31k views

How to create VHD disk image from a Linux live system?

Once more, I have to resort at the experts here at SuperUser, as my other sources (mainly Google ;-)) didn't prove very helpful... So basically, I would like to create a VHD image of a physical disk ...
2
votes
1answer
1k views

Linux DD command partition -to- partition

I just used the DD command to copy the contents of one partition over to another partition on another drive, like this: dd if=/dev/sda2 of=/dev/sdb2 bs=4096 conv=noerror sda2 partition was 66GB and ...
16
votes
4answers
33k views

Why does 'dd' not work for creating bootable USB?

Recently I wanted to create a bootable USB of Linux mint. I found that there was a lot of conflicting advice/experience about whether the 'dd' command could be used to create a bootable USB. I decided ...
3
votes
4answers
4k views

Windows XP virtual machine hangs in VirtualBox

What i want to do: I'm trying to virtualise 2 different physical Windows XP systems which reside on one hard drive each to VirtualBox under Windows 7. What I did (once per drive): From a Linux ...
2
votes
1answer
321 views

Getting position of track and sector in 'dd'-created floppy image

I got some floppy images (original DOS 6.22 und FreeDOS 1.44 MB boot disks) created using the *nix ddcommand that work fine when used in a virtual environment. Now I want to understand the structure ...
0
votes
0answers
254 views

Clone Image Without Empty Blocks

I've been using dd if/mnt/sda1/images/$1 of=/dev/$2 to clone some embedded images for compact flashes. I used to only be using one brand of CFs, but, now I have two of them (both 2g, but obviously ...
1
vote
1answer
307 views

Copy existing Ubuntu drive to partition on new hard drive

I have a new laptop with two partitions, one is currently loaded with Windows 7, the other is blank. I'm pretty familiar with using dd to backup/copy drives, but I'm wondering how I will deal with ...
1
vote
1answer
461 views

Do Linux swap partitions need to be cloned?

I'm in the process of cloning my hard disk in order to test some unstable software. One of the partitions is Linux-swap. From my understanding, it can be used by the os as additional ram. So this ...
3
votes
2answers
2k views

What is the difference between dd's direct and fsync options?

I would like to copy an image to a USB thumb drive. As I would like to get "real" speeds, and don't want to wait ages for the device to sync after copying the image, I would like to know which ...
1
vote
4answers
277 views

Can I dd from my current hard drive to another hard drive while running the OS

My initial thought is that this is a bad idea. But let's assume that I can't take a USB stick into my lab to run a live-Linux distro, and my computer has only 2-SATA ports. I have one 80GB SATA drive ...
2
votes
4answers
5k views

How to output file from the specified offset, but not “dd bs=1 skip=N”?

How to do thing like dd if=somefile bs=1 skip=1337 count=31337000, but efficiently, not using not 1-byte reads and writes? The solution is expected: To be simple (for non-simple I can write some ...
6
votes
1answer
2k views

Compressing a file in place - does “gzip -c file | dd of=file” really work?

In the question How can I compress a file on Linux in-place, without using additional disk space?, one answer proposes to simply use gzip -c file | dd of=file I tried it (on Debian Linux), and it ...
4
votes
1answer
750 views

Can you successfully clone a Mac OS X boot volume directly to another larger volume with ddrescue?

Can you clone a Mac OS X boot volume (specifically a "Mac OS Extended, Journaled" a.k.a. JHFS+ volume) directly to another, larger volume using ddrescue or even dd, and have the target volume end up ...
3
votes
1answer
485 views

Checking if any data exists on a presumably empty storage device

So, say you've completed a full pass of: dd if=/dev/zero of=/dev/sdX bs=1M Then, you'd like to make sure the destination has been really zeroed out (ignoring the confirmation messages from dd ...
0
votes
2answers
379 views

Copy just the 64 byte partition table using dd

Given: ===MBR INFO=== MBR SECTOR NAME BYTES code area 440(max. 446) disk signature (optional) 4 Usually nulls; 0x0000 2 Table of primary partitions 64(Four ...
1
vote
0answers
343 views

Is it possible to repair iso images incorrectly made with dd in OSX Snow Leopard?

About a year ago, I made rips of a bunch of my CD/DVD games and packed the originals away. The problem is that now I'm trying to use WinXP Pro on VirtualBox on OSX Snow Leopard to play these iso ...
1
vote
1answer
159 views

Multiple /dev entries for the floppy drive, can not write to drive

I have an old computer that I am trying to use to write to a floppy. It is running Ubuntu 10.10 and is a Dell. Every time I try to mount the floppy drive, it fails (probably because I don't know the ...
10
votes
3answers
17k views

How do I create an MBR on a USB stick using DD command line tool

Okay I'm trying to create a BOOTABLE Windows7 image on a USB key from a Mac running Lion. My image is .iso format. I tried: sudo dd if=/Users/myusername/Win7.iso of=/dev/disk1 bs=1m And this ...
1
vote
0answers
70 views

Maintaining peak IO potential with DD / CP

I wanted to copy a file (40 gig dataset) from a single drive to a dual disk raid-0 drive. I tried with CP and it sustained read - 4mb and write - 11 mb (doesn't make sense I know (must be the stripe ...
2
votes
1answer
921 views

What is the difference between ghost and dd?

When I back up from one hard drive to another with Ghost I can switch those hard drives at will and the computer doesn't seem to mind. When I back up HDD A onto HDD B with dd, HDD B performs slower ...
18
votes
5answers
13k views

Why is my /dev/random so slow when using dd?

I am trying to semi-securely erase a bunch of hard drives. The following is working at 20-50Mb/s dd if=/dev/zero of=/dev/sda But dd if=/dev/random of=/dev/sda seems not to work. Also when I ...
1
vote
1answer
136 views

how to recover my hard drive…put an iso image on it with dd

I did the following: dd if=some.iso of=/dev/sda Or some such craziness. How should I recover from this? Gparted, etc..., didn't help out, deleting partition etc... Whenever I try to install a ...