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

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1answer
4k views

dd_rescue vs dcfldd vs dd

What are the main differences between dd_rescue, dcfldd, and dd? In what situations would you use one over the other? Why are there three different yet simliar programs?
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2answers
13k views

How to copy an ISO image onto USB with dd

The last paragraph of the SliTaz 3.0 Release Notes says the following about the liveCD: The ISO image now uses a 'hybrid' system: it can also be copied onto an USB stick without formating it ...
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1answer
235 views

Can I use dd to clone two drives from two machines simultaneously?

To clarify, I have two machines: Machine1 and Machine2. Each machine has 2 disks (Machine1 has Disk1-1 and Disk1-2; simiarly, Machine2 has Disk2-1 and Disk2-2). Can I use 'dd' to clone Disk1-1 to ...
3
votes
2answers
8k views

Rescuing a hdd with bad sectors: dd vs gddrescue

Somewhere on the internets I read that gddrescue is superior to dd at least in terms of being able to distinguish between the amount of disk reads performed on a troubled sector. Is this really the ...
1
vote
1answer
300 views

Does `dd` on a device skip anything?

I wanted to achieve a system disk backup with an Ubuntu live CD. I used the following command: dd if=/dev/sda conv=sync,noerror bs=64K | gzip -c > /media/external/image.gz This seemed to work. ...
2
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2answers
1k views

Reading from the end of a drive with dd

How can I read from the end of a drive with dd? I thought about using size - to_read but I have no idea how to get the size in bytes.
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votes
2answers
7k views

How can I mount a disk image?

I have a disk image myimage.disk which contains the partition table and a primary partition (i.e. a FAT32 filesystem). Think that as a USB pen image. I want to mount the primary partition to a local ...
4
votes
1answer
623 views

Trying to create an ISO of my bootable USB using the unix command: dd

i'm trying to create a (bootable) ISO (which i'll then burn to dvd) from the source being an bootable USB disk (it contains windows 7 and i've installed a number of PC's from it already). So i'm ...
4
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2answers
471 views

Recovering Ubuntu after filesystem was overwritten using dd

I had an Ubuntu installation on my laptop, on an encrypted LVM (this was /dev/sda1). I was planning to write an Arch Linux image to my USB drive (/dev/sdc1), following this guide - ...
0
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3answers
700 views

How can I copy my Mac's entire hard drive to an external hard drive?

I want to copy my entire hard drive to an external hard drive of equivalent size. I'm using a Mac, and I was thinking about booting Ubuntu so that I can use dd, but I'm not sure how to do that. If ...
2
votes
2answers
924 views

How to make a floppy image and overwrite the MBR

I am trying to make a floppy image with a working file system so that I can test a 2 stage boot loader. When I attempt to mount the floppy and then cp the second binary over to it, mount gets all ...
2
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0answers
327 views

Why does my disk ignore erase and write commands to some sectors?

I did an ATA secure erase on an SSD (with SystemRescueCD and hdparm). Some parts of the disk are reset to zero, but some parts are not. In particular, the MBR and the boot sector of a Windows Vista ...
1
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2answers
394 views

The 'real', 'user' and 'sys' description from time(1) differ when they shouldn't?

I read this SO question on 'real', 'user', and 'sys' descriptions and thought I'd play a little. Can someone explain why [root@lux ~]# time dd if=/dev/zero of=del.large bs=10K count=32768 32768+0 ...
0
votes
1answer
1k views

Mount part of a dd image as a truecrypt volume

I have a dd image of a full drive (as a file) that was using Truecrypt system encryption under windows. I want to mount the main partition from that image using Linux's Truecrypt. I am familiar with ...
4
votes
1answer
3k views

Using dd with bad blocks on a harddrive?

I'm looking to use dd to make a clone of failing harddrive. My concern is there will be bad blocks for surely. So my question is with dd will a bad block leave a gap the size of the selected ...
3
votes
1answer
2k views

How to do a hexdump of first track of HDD?

How would i do a hexdump in Ubuntu for the first track of a HDD? I am looking for a winhex-esque output if that makes sense. The first track has 63 sectors, each 512 bytes long. I tried dd ...
0
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1answer
1k views

How to wipe one sector with DD?

What is the dd command in Linux for securely wiping sector 62 of a hard drive. This sector lies in track zero, begins at offset 31744 and is 512 bytes long. I'd like to know how to wipe it over 1000 ...
1
vote
1answer
871 views

How to make a partition if I have a partition.img file?

I have an Acer laptop I've been toying with, at some point I backed up the 'Acer recovery' hidden partition using dd. iirc I used a LiveCD and something like: dd if=/dev/sda1 of=/mnt/remote/acer.img ...
0
votes
1answer
4k views

osx sudo dd if=/dev/disk0 of=/dev/disk1

Am I doing this right? The process isn't very verbose I am upgrading my HDD, I have a larger external drive I want inside my macbook. I want to copy the contents and partitions of my internal mac ...
5
votes
1answer
3k views

Can I resume an interrupted disk image done with dd?

I am going to reinstall my system and I want to backup it first. There is an 80 GB HDD with Ubuntu and 750 GB HDD on which I want to put image. So, I run a live CD and use dd to transfer my sda to ...
0
votes
1answer
2k views

How to boot dd image in QEMU?

I created an image of my Debian Squeeze running on a Sheevaplug using dd if=/dev/sda of=plug_SD-karte.img (sda is the SD card plugged into another computer). Now I want to emulate the Sheevaplug. I ...
2
votes
4answers
261 views

Can I copy the Macintosh HD to migrate my data to a new Mac?

I want to get a new Mac. Can I simply dd a disk image from my older mac's hdd to the new Mac with a bigger HDD (this will be further partitioned, but the old osx drive will fit within one OS X-style ...
2
votes
1answer
176 views

cleanup after “dd” operation

I'm using dd with "excl" option. If interrupted with CTRL+C "dd" leaves the the file it has created and not finished to write. I need to clean it up in such case with the trap INT. However, I don't ...
0
votes
1answer
2k views

How to create an image.dd file to be used in virtualbox?

I want to backup my Windows machine before I put Ubuntu on the hard drive instead. Following the instructions on the VirtualBox website it says to create an image.dd file using dd. I booted up from ...
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3answers
13k views

How to pad a file with “FF” using dd?

How to pad a file with 0xFF using dd? This command will pad the output file with zeroes until the file size reaches 100 KB: dd if=inputFile.bin ibs=1k count=100 of=paddedFile.bin conv=sync ...
2
votes
1answer
345 views

What number of bytes should I set the bs to in the dd command?

I have just created a usb boot disk so that I can install Fedora 14. I used the following which was successfully. However, I am left wondering what does the bs parameter actually does. I know it mean ...
2
votes
1answer
299 views

wipe disk with dd

I know we can wipe a hard disk using random data or zeros, but is it possible to wipe using a fixed string ? e.g. is this correct? dd if="string" of=/my/harddisk ... Also, does the options below ...
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5answers
841 views

Is it a very bad idea to create disk image of mounted disk?

I would like to backup my server. For example using dd: dd if=/dev/md0 of=/some_network_share I wonder if this image will be vary inconsistent if /dev/md0 is mounted? Would it be possible to ...
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3answers
2k views

OSX: can I dd a usb thumb drive into a file?

I have mounted a usb thumb drive into my MBP. Here is the partial output from mount /dev/disk2s1 on /Volumes/KINGSTON (ntfs, local, nodev, nosuid, read-only, noowners) When I tried $ dd ...
0
votes
1answer
434 views

“Target filesystem doesn't have sbin/init” after cloning boot disk with dd

I cloned a boot disk (bootloader, / and swap partitions) with dd to the same size disk (bad sectors started to appear). Got 1 reading error in the middle of the disk. After I swapped the disks I ...
4
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2answers
4k views

How to Copy .VHD File to Physical Hard Disk Using DD Command

I have read other question/answers on this site that say this is possible, but I'm wondering how it is done. I have tried the following command, which completes successfully, but the NTFS isn't valid ...
2
votes
3answers
468 views

Advice on cloning disk

I'm going to buy a second disk for backup, the same size as my laptops. I want to mount it in a casing via usb and backup an entire hdd every soemtime. That's because I want the posibility to just ...
1
vote
1answer
735 views

Why does my dd backup of MacBook OS X fail to boot upon restore?

I created a backup of a MacBook hard drive (WD2500BEVS-88US) by hooking it up as a secondary drive on my linux system (Ubuntu 10.10). I used the following command: sudo dd if=/dev/sdc ...
2
votes
2answers
487 views

What does dd do when the destination drive runs out of space?

I tried to make a drive image using ddrescue, but I'm not sure if the destination drive had enough space. Does dd just silently continue to try writing to the drive even when it has run out of space? ...
5
votes
1answer
543 views

dd gets slower while reading and writing

user@user-laptop:~$ sudo dd if=sd_backup of=/dev/sdd bs=4M conv=noerror,sync 205520896 bytes (206 MB) copied, 28.564 s, 7.2 MB/s 247463936 bytes (247 MB) copied, 57.1285 s, 4.3 MB/s 260046848 bytes ...
2
votes
1answer
168 views

Looking for advice on using dd to backup a dual boot laptop

My questions boils down to this. If I do "dd if=/dev/sda of=usbdrive" can anybody confirm that this will get everything including mbr/partition information/all four partitions and create a drive that ...
4
votes
2answers
1k views

faster dd backup by differential copy

im looking to use dd to back up my whole hard drive regularly but it takes around 1.5 hours and want to know if there is a faster way to back up. possibly just by updating the bytes which are ...
2
votes
2answers
158 views

saving data from a failing 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 ...
11
votes
5answers
6k views

How to erase a hard drive with unwritable sectors?

So I have a hard drive that is failing. I want to erase the data on it before sending it for replacement. I'm trying to use dd if=/dev/zero of=/dev/sdXX, but it stops at the first write error. How can ...
2
votes
1answer
230 views

Cloning a Windows partition through unix

my boot disk has chameleon installed with a linux partition and a second, empty partition that I would like to use with Windows7. Since you never know how much things will Win7 ruin when installing I ...
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vote
4answers
269 views

Creating an image of my hard drive

I've been thinking of making an image of my laptop's hard drive for backup purposes. What would be the best way of doing this? I know about dd but is there a more user-friendly way, perhaps a GUI ...
9
votes
7answers
3k views

How can I recover a crashed hard drive?

My hard drive from my MacBook crashed and died hard last week. I replaced the drive with a new one, and installed 10.6/Snow Leopard on it. The old drive is now in a usb enclosure, and I really need to ...
3
votes
3answers
371 views

Backing up to smaller drive

In a few hours I'll have a new 500GB Sony laptop, filled with the usual Sony rubbish which I'll promptly be replacing with Ubuntu or Crunchbang or something. However, first I want to make a full clone ...
0
votes
1answer
2k views

Is there a way to obtain the raw image from a Norton Ghost file?

I have a Norton Ghost .gho file, and basicly I want to extract the raw image out of this, for example to use with with tools like dd. (So using any symantec/windows tools is not an option). Is there ...
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2answers
3k views

Which way is the fastest to `dd` to the last 512 kilobytes of disk

I have a 512G disk and I want to clear the last 512k bytes at the end of the disk. I usually clear it by dd if=/dev/zero of=/dev/da0 the whole disk. Which way is the fastest to do this operation?
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vote
2answers
272 views

Harddisk formatting with dd return error

I tried to format my harddisk (160 GB) with the following command dd if=/dev/zero of=/dev/sda After some 3 hours, following error came up: dd: writing to '/dev/sda' : No space left on device ...
17
votes
5answers
19k views

How Do I Find The Hardware Block Read Size for My Hard Drive?

I'm trying to figure out the optimal size for a large copy from my hard drive using dd. I'm trying to figure out what the best blocksize to use it, which I would assume is the hardware block size for ...
19
votes
4answers
24k views

How can I find what /dev my DVD-drive is?

I'm on Mac OS X, have a DVD in the DVD-drive and can look at it in the Finder. I'd like to try to create an iso of it by using the dd command. But to do that I need to know what device to use as an ...
3
votes
5answers
1k views

dd producing corrupt ISO images on Snow Leopard (whether invoked from a script or the shell)

Alright, I am probably being an idiot here, but I am writing an ISO-ripping util that is really just GUI slapped on top of dd, and I can't coax the thing to produce non-corrupt ISOs on Snow Leopard. ...
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1answer
1k views

Restoring a HDD backup image from the Ubuntu Live CD

I want to restore a HDD image I have to my laptop's HDD while booted off the Ubuntu Live CD. The laptop's HDD is unformatted and has no partitions. I expected this to work: $ sudo dd ...