dd is a traditional utility for binary data copies

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DD to a bigger partition

So I made a backup of /dev/sda1 (NTFS) using: sudo dd if=/dev/sda1 conv=sync,noerror bs=64K | gzip -c >/media/My\ Book/backup/Root20131215 In the meantime I increased the size of /dev/sda1 to ...
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1answer
27 views

Can I uncompress a zip file containing a disk image and then save that to an SD card all in one step?

I am under the following restrictions: I have a 1.0 GB .zip file on my computer which contains one file, a disk image of raspbian. When uncompressed, this file is 3.2 GB large and named ...
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2answers
74 views

Is it better to use cat, dd, pv or another procedure to copy a CD/DVD?

Background I'm copying some data CDs/DVDs to ISO files to use them later without the need of them in the drive. I'm looking on the Net for procedures and I found a lot: Use of cat to copy a ...
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14 views

testdisk foremost dd photorec after math help needed

Did i ask this question in the wrong place the first time? http://superuser.com/questions/957845/how-can-i-efficiently-view-validate-delete-1m-files-from-data-recovery I made such a long post about ...
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1answer
19 views

Broken disk size after incomplete dd operation

Once I was writing an ISO image into my USB disk using dd, I mistakenly pulled it out, and now it has only 10 MB of size. The correct size is 32 GB. Note that this smaller size is for the whole USB ...
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18 views

Write shrunken .img file to device file

I have a backup image of a device file /dev/sda3 that I created using: dd if=/dev/sda3 of=~/sda3.img. The image is very large, so I have re-sized it to remove empty space. My question is can I ...
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2answers
57 views

Interpreting dd Input/Output error

I tried to copy /dev/Storage/Storage (an LV under LVM) to an image file using a dd | pv | dd pipeline. dd reported an error, and I want to know whether dd finished copying my disk or stopped due to ...
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10answers
51k views

How do I know if dd is still working?

I've not used dd all that much, but so far it's not failed me yet. Right now, I've had a dd going for over 12 hours - I'm writing an image back to the disk it came from - and I'm getting a little ...
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2answers
846 views

Why does dd from /dev/urandom stops early? [duplicate]

On my current Linux system (Debian Jessie amd64), I'm getting different behavior for dd using /dev/urandom (/dev/random behavior is properly documented). If I naively want 1G of random data: $ dd ...
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24 views

Backup full drive structure, skipping one partition content

I need to backup laptop drive. But in fact what matters is not data as in my data files kept on laptop but all systems, settings, lvm and in general whole disk structure - partitioning, UUIDs, LUKS ...
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3answers
5k views

Why can't I copy my DVD with dd?

I tried dd, dd_rescue and ddrescue, all failed. I thought these tools bypass the filesystem and make a bitwise copy. dd is fooled, it finishes but just produces a small file and states it's finished. ...
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3answers
99 views

Does dd copy everything, including all metadata and all “empty” blocks

Suddenly something was messed up with my partitions, or just one partition. I have a default Ubuntu installation, on a Kingston SSD, with the root file system encrypted with LUKS, (using AES I think). ...
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7answers
12k views

dd vs cat — is dd still relevant these days?

I recently realized we can use cat as much as dd, and it's actually faster than dd I know that dd was useful in dealing with tapes where block size actually mattered in correctness, not just ...
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7answers
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How do I suppress dd output?

I have a bash script that creates some file using dd. The problem is dd throws a great amount of output that is going to mess with the output of my script. Searching around I've found a solution: dd ...
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1answer
56 views

RAID mdadm virtual disk too small

sudo mdadm --build /dev/md0 --level=linear --raid-devices=3 /dev/loop0 /dev/sda1 /dev/sda2 After running the above command, /dev/md0 is smaller than /dev/loop0 + /dev/sda1 + /dev/sda2. Why is that ...
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5answers
4k views

Comparison of raw block devices

Is there a utility (or some shell magic) that allows me to compare two block devices? Details: I have one large (0.5 TB) RAID device that I've backed up to a slightly larger SATA device using dd. ...
2
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1answer
36 views

using dd command for folder, but deleted items don't seem deleted [closed]

here is the image I used dd command to create a new floppy. First I tried it with a folder filled with naber.bin, test.bin, blabla.bin and boot.bin. And then i deleted all except boot.bin. ls -a ...
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3answers
92 views

How can I copy three partitions of my disk with a specific beginning and ending using dd?

Using the fdisk -l command I got the following answer: Device Boot Start End Blocks Id System /dev/sda1 * 2048 28266495 14132224 27 Hidden NTFS WinRE ...
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5answers
61 views

How one can re-read image with dd so it will match one you just wrote?

I have a ~1GB image that I'm writing to a 8GB SD card via the dd tool. I'd like to verify that it was written without corruption by reading it back and comparing its hash with original one. ...
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2answers
1k views

Patching a binary with dd

I have read this quote (below) several times, most recently here, and am continually puzzled at how dd can be used to patch anything let alone a compiler: The Unix system I used at school, 30 ...
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3answers
922 views

how to use dd to fill drive with 1's

Filling a drive with /dev/urandom seems to be very slow, so I created a file filled with FF: dd if=/dev/zero ibs=1k count=1000 | tr "\000" "\377" >ff.bin I'd like to fill the drive with copies ...
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1answer
26 views

how to use dd to backup second linux hard drive from os x?

I have a MacBook with Linux installed on the primary hard drive. On an external USB 3.0 drive, I have OS X installed. The external drive has plenty of space so I would like to boot up OS X and make ...
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4answers
194 views

How can I convert two-valued text data to binary (bit-representation)

I have a text file with two (2) only possible characters (and maybe new lines \n). Example: ABBBAAAABBBBBABBABBBABBB (Size 24 bytes) How can I convert this to a binary file, meaning a bit ...
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0answers
40 views

osx - dd command behaving weirdly [duplicate]

I've been using dd for a couple of years now, most of the time successfully. I usually use it to dd Linux images to USB drives. My workflow doing so is as such: convert .iso image to a .img format ...
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1answer
54 views

How to write to an .img file with two different partitions?

I have been working on building a Linux based OS for Raspberry-pi using buildroot. I am generating the required empty .img file using "dd" and "fdisk" utilities. I am creating two empty partitions ...
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2answers
83 views

What is actually the speed reported by dd?

I always thought that when doing: dd if=/dev/sdx of=/dev/sdy the report which is displayed once the command finishes, such as: 79304319+0 records in 79304319+0 records out 40603811328 bytes (41 ...
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1answer
63 views

How to clone an MTPFS partition of a mounted Android phone?

Using mtpfs I've mounted a Samsung Galaxy S5 and I need to make an image of its root partition. I want to use dd or the like, but nothing seems to be able to detect/reference an MTP and/or FUSE ...
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4answers
19k views

Is there a way to determine the optimal value for the bs parameter to dd?

On occasion I've seen comments online along the lines of "make sure you set 'bs=' because the default value will take too long," and my own extremely-unscientific experiences of, "well that seemed to ...
3
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1answer
51 views

Size difference between an iso file burnt to a cd and the file retrieved with dd

I have an iso file (foo.iso) that I burnt to a dvd with the command : growisofs -dvd-compat -Z /dev/cdrom=foo.iso I then tried the command dd if=/dev/cdrom of=foo2.iso However, foo2.iso is ...
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How to dd a remote disk using SSH on local machine and save to a local disk

How can I create a backup of a remote disk using SSH on my local machine and save it to a local disk? I've tried the following: ssh hostname@my.ip.address "sudo dd if=/dev/sdX " | \ dd ...
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1answer
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cant run dd command on android device

The main objective is to send a splited file to an android and join it back up with a .sh script, the file is splited to 5MB parts but its total size is unknown (trying to make an universal script), ...
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58 views

Making an ISO of MBR + X amounts of partitions

I am trying to make an ISO of a Windows Backup disc that I "burned" to my microSD card, which I did in desperation due to lack of HDD storage at the time. Now I want to get it out of there and onto ...
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5answers
25k views

Is it possible to mount a gzip compressed dd image on the fly?

I like create an image backup for the first time I'm backing up a system. After this first time I use rsync to do incremental backups. My usual image backup is as follows: Mount and zero out the ...
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1answer
43 views

Hard Disk Clone Image Size

I've created an image backup for HDDA (partition) from HostA and saved on HostB ssh -c blowfish user@ip-or-hostname "dd if=/dev/sda1 | gzip -1 -" | dd of=sda1.gz conv=sync,noerror The HDD size is ...
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3answers
503 views

DD and Free Space

I have a partition (/dev/sda1) of 10 GB. Also have "dd" file of another 7 GB partition ( /dev/sdb1). When I execute the command as: dd if=sdb1.dd of=/dev/sda1 then everything goes fine but I ...
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28 views

Can't figure out what all these sd drives are

So I created a WindowsXP install using an NTFS drive in VMPlayer and now I want to make an image of it using dd. Here is the diskpart info from Windows: Then I use Kali as a live-cd and I find like ...
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1answer
156 views

dd shows a random number of records in/out [duplicate]

I'm writing some images back to block devices, with dd, and getting very strange output I've never seen before. # xz -dc goren.img.xz | dd bs=1M of=/dev/storage2/goren 35+2475166 records in ...
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4answers
2k views

Why is writing SLOW on raw device, and FAST on filesystem (USB key)?

I have a USB key (PQI U822V-Speedy 32G) that I am trying to benchmark quick'n'dirty on Linux. I'm testing write bandwith. dd on raw partition I created a partition starting at sector 2048, then did ...
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2answers
92 views

Writing ISO file to USB

I need to write a windows7 iso file on my usb stick. I had been used to this task. I usually either use the dd tool, or unetbootin. Surprisingly both don't work today. With dd I did the following : ...
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1answer
29 views

How to image certain portions of hard drive only

I have a failed hard drive which I need to extract data from. My dd kung fu is failing me right now. I know that the drive is failing at sector 60515007 to 60517093 (512b per sector), and multiple ...
4
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1answer
319 views

Write the same file multiple times to one file using dd

I am trying to create large dummy files on a drive using dd. I am currently doing this: #!/bin/bash writeFile(){ #$1 - destination directory/filename, $2 - source filepath $3 - blocksize, $4 - ...
3
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1answer
42 views

How to inspect the raw contents of a partition?

I'm trying to see the contents in raw bytes of a dummy partition /dev/sda3, which I've made to be 100MiB through gparted. I want to test writing and reading on that partition. Is there a tool that ...
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4answers
465 views

How to pad a file to a desired size?

I have a file that I want to pad until it reaches 16 MiB (16777216 bytes). Currently it is 16515072 bytes. The difference is 262144 bytes. How do I pad it? This doesn't seem to be working: cp ...
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4answers
164 views

Change only one bit in a file

I have to test a hash function and I want to change only a single bit of a specific file. I tried with the dd command. That works, but I can only change a whole byte and not just a bit. sudo dd ...
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0answers
41 views

What are the [internal] steps involved in making USB drive 'bootable'?

Whenever I have to install a new Linux distro, I create a bootable USB from the distro image using some specialized program like UNetBootin. Recently, I tried to do for Fedora using 'dd' command, but ...
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2answers
253 views

Multiple passes of wiping disk with `dd`

I want to use dd to overwrite a disk multiple times to destroy data beyond recovery. I know I could use dd if=/dev/zero/ of=/dev/sdx/ to do a pass with zeros, or dd if=/dev/null/ of=/dev/sdx/ to ...
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5answers
4k views

Fast Way to Randomize HD?

I've read about how to make hard drives secure for encryption, and one of the steps is to write random bits to the drive, in order to make the encrypted data indistinguishable from the rest of the ...
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424 views

USB Stick recognized but not mountable

I have a USB Stick which is recognized by my laptop but there is no partition to mount. The device is listed in /dev/ as sdb but no partition /dev/sdb1. fdisk -l also displays nothing about /dev/sdb. ...
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1answer
88 views

Syntax When Combining dd and pv

I am a linux newbie; so, sorry if this is obvious to you... sudo dd if=/dev/sda bs=64k | pv --size 1.5t | dd of=/dev/sdb Does the block size for dd go on the left side of this after the input as ...
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1answer
85 views

From a sparse file to a block device

I have a system image sparse file which actual size is only a few MBs but the "apparent size" is about 1GB. I'm trying to write it to a block device efficiently (without the holes). Here are some ...