dd is a traditional utility for binary data copies

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1answer
27 views

How can I check if a dd disk image is consistent (i.e. not corrupt)

I have a dd disk image. How can I check if it is consistent? (It doesn't have to be an exact copy.) I am trying to run extundelete, but I don't know if it's failing because the underlying ...
2
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3answers
113 views

dd crashing - what to do about it

I have dd crashing after running a few hours. Typically with a message like Input/output error 68424+1 records in 68424+1 records out 342124883968 bytes (342 GB) copied, 5114.68 s, 66.9 MB/s Is ...
0
votes
1answer
50 views

How do I create a dd IMAGE from LVM for recovery purposes [duplicate]

How do I backup a LVM partition to an image for recovery purposes? I am trying to run dd on /dev/sda2, but it crashes after ca 8 hours, at around 380G sudo lvmdiskscan /dev/centos/swap [ 3....
0
votes
1answer
19 views

Restore unencrypted LVM2 logical volumes to LVM on LUKS setup?

I have an unencrypted Ubuntu 16.04 setup using LVM2. I'd like to 'port' this into an encrypted setup on the same computer and disk, which would save me the hassle of reinstalling all the apps and ...
0
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0answers
6 views

How to create BitDefender rescue USB drive from Elementary OS?

As the title says. I am a Linux noob and can't seem to find an app to do this. I have tried using Unetbootin and on boot I got the following error: linux.c32: not a com32r image Google tells me ...
0
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1answer
35 views

Can backups of root mounted to a logical volume be restored to a larger logical volume?

My current Ubuntu setup has root mounted to a LVM2 logical volume 'lvroot'. lvroot is 10G. I've been taking snapshots of lvroot, and then making dd backups of the snapshots (which creates a backup of ...
0
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1answer
27 views

dd no such file or directory

I've booted up arch live cd, with the idea of creating a disk image. There are 2 hdds (/dev/sda - i want this image, and /dev/sdb - the image will be copied here, but as a backup file (not rewrite), ...
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0answers
36 views

dd does not work for an image created in freebsd 9.3

I tried to dd the image created in freebsd 9.3 $ sudo dd if=test.img of=/dev/disk2 bs=1m Password: 0+0 records in 0+0 records out 0 bytes transferred in 0.000010 secs (0 bytes/sec) This works in ...
1
vote
1answer
25 views

Mounted devices when using dd to create USB device boot image

I have read that when creating a USB boot image with dd, the USB device should not to be mounted. Can somebody explain to me why not? I am very confused please help me out.
0
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1answer
41 views

raid 0 recovery after accidental dd to disk [duplicate]

I have 3 HDD's: /dev/sda and /dev/sdb (2x1TB) both on RAID 0 mode -> /dev/md127, and 4TB /dev/sdc, -> /dev/sdc. Accidentally I ran dd script from https://github.com/tdg5/blog/blob/master/_includes/...
5
votes
1answer
47 views

Why is fragmentation level so huge in files that contain other filesystems?

I've just found out what sparse files are and wanted to conduct some experiments on them. On wiki you can read that the files can get fragmented easily. I wanted to check how bad that is. I created a ...
2
votes
1answer
50 views

Understanding sparse files, dd, seek, inode block structure

At work we use sparse files as part of out Oracle VM environment for the guest disk images. After some questions from a colleague (which have since been answered) I am left with more questions about ...
-3
votes
1answer
26 views

why does does windows run checkdisk after I clone into a vm disk it using dd? [closed]

I decided to create a vm image of one of the windows desktops using the following commands in ubuntu live cd. /dev/sda is the windows drive to backup. /dev/sdb is the extra drive to store the image. ...
4
votes
1answer
155 views

Use backup file from dd to restore hard disk and also extract files

I made regular complete backups of my hard disk (with all partitions) using dd tool as backup.img file. I have several such files. Now that my old hard disk died, how can I use backup.img file to ...
13
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2answers
677 views

dd: write to multiple disks?

I have 2 exactly same formatted, same size and same brand SD-cards. I would like to dd image to /dev/disk2 and to /dev/disk3 at the same time. Pseudocode sudo dd bs=1m if=/Users/masi/2016-05-10-...
0
votes
1answer
34 views

Full system backup with dd include symlinks

I'm really new in unix and Linux and just tried to learn something. My question is how can I make full system image/backup with dd include symlinks? Is dd good or I should use another approach? Can ...
1
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2answers
44 views

Can't clone hard disk with dd no space left

I am trying to move elementary OS from primary HDD to external HDD. So, I can boot elementary OS from external HDD and install Windows 10 on primary HDD. Hewbot on super user stackexchange suggested ...
0
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1answer
31 views

Sometimes syncing gets stuck with dd

Sometimes when I use dd then sync or use dd with conv=fsync, the syncing process gets stuck, but sometimes not, with exactly the same input and output targets and configuration. dd if=2016-03-18-...
13
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4answers
721 views

dd: multiple input files

I need to concatenate chunks from two files: if I needed concatenate whole files, I could simply do cat file1 file2 > output But I need to skip first 1MB from the first file, and I only want ...
0
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0answers
19 views

How do I create an bootable UBCD-stick using FreeBSD?

I have an UltimateBootCD-image-file (iso) and I want to create a bootable usb-stick from it. I tried dd'in it, % dd bs=4M if=/path/to//ubcd.iso of=/dev/da0 && sync 103+1 records in 103+1 ...
1
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2answers
72 views

What's the POSIX way to read an exact number of bytes from a file?

Just hit this problem, and learned a lot from the chosen answer: Create random data with dd and get "partial read warning". Is the data after the warning now really random? Unfortunately ...
2
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2answers
77 views

Terminal: create bootable USB from iso

How can I create a bootable USB stick from an iso image? I thought dd should do the work, but so far I were unsuccesful. This is what I've tried: umount /dev/sdx deleted every partition on sdx ...
0
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1answer
43 views

Update Dell Latitude BIOS with “dd” command rather than “UNetbootin”

I'm doing these instructions. I cannot use UNetbootin, therefore I'm trying dd command instead: sudo dd if=~/Downloads/fdbasecd.iso of=/dev/sdc bs=10M After dd, the filesystem of bootable USB is ...
0
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0answers
54 views

Why does hdparm and dd show two completely different results?

I have an external hard drive (/dev/sdc1) mounted at /mount1 When running hdparm -tT /dev/sdc1 I get: /dev/sdc1: Timing cached reads: 2246 MB in 2.00 seconds = 1123.75 MB/sec Timing buffered ...
0
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3answers
48 views

Modifying a byte with bash, dd isn't working

I'm trying to modify a byte with bash, So I will write the bytes before the offset, then the byte to modify, and the rest of the file. But the following script doesn't work as expected Anyone ...
2
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2answers
48 views

Efficient Use of dd (buffer many blocks, process one at a time)

Given a file, I need to search for the number of blocks that matches an input block $templateBlock of certain size $blockSize. What is an efficient way to use dd to accomplish this task? The ...
4
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4answers
1k views

What is this dd if=/dev/zero of=/dev/sda do

Could someone help me understand what I got? dd if=/dev/zero of=/dev/sda bs=4096 count=4096 Q: Why specifically 4096 for count? dd if=/dev/zero of=/dev/sda bs=512 count=4096 seek=$(expr blockdev --...
0
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1answer
40 views

SSHD cloning - something special to keep in mind, compared to HDD?

The question is whether the fact the device is a hybrid disk has any (and what) importance when using dd or other such tools, or if all operations run the same as for a HDD. The context The device ...
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0answers
36 views

How to image a CentoS 7 i386 ISO to a USB device?

Usually if I want to image a CentOS 7 ISO (or any Linux ISO for that matter) to a USB device, I do this via dd as follows dd if=CentOS.iso of=/dev/sdX bs=8M However I've tried this method with a ...
0
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1answer
54 views

Running dd. Why resource is busy?

I just formatted microSD card, and would like to run a dd command. Unfortunately dd command fails: $ sudo dd bs=1m if=2016-02-26-raspbian-jessie-lite.img of=/dev/rdisk2 dd: /dev/rdisk2: Resource busy ...
1
vote
1answer
29 views

How to clone an entire disk to a larger disk and then offload?

The title might be a bit confusing, so in detail: What I have done is clone a small 32GB flash module that had three partitions. I happened to have a 32GB USB lying around, so I thought it might just ...
4
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0answers
16 views

Looking for a way to backup/mirror a drive by swapping

I want to duplicate a drive. I am unable to hook up both the old and new drive at the same time (the old powerbrick died; so I have one powerbrick to swap between two drives). In years and years ...
1
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0answers
59 views

BASH dd problem

i am trying to learn bash and now im trying to do a script for burning isos. I made the number "4" command to make sure the variables were right. the message i get when i complete my program and ...
1
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2answers
36 views

Can I use dd to move my system to another partition?

Currently, my whole system is located at the end of my hdd. I'd like to move that data to the beginning and still have booting and other details working. dd seems to do exactly what I want (to copy ...
1
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0answers
59 views

how to copy a piece of a text file byte-by-byte to another text file? dd, head, or?

I need to grab the first lines of a long text file for some bugfixing on a smaller file (a Python script does not digest the large text file as intended). However, for the bugfixing to make any sense, ...
0
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3answers
88 views

dd show 'raw' progress while piping output

I am attempting to perform a specific dd operation and appending 'raw' data of the transfer to a log file which will be polled by something else, to provide a live view of the transfer on another ...
0
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1answer
22 views

Restore a disk from a snapshot in XEN 4.6

I created a snapshot with lvcreate -n snap01.vm01 -L 5G -s vg0/vm01.eclabs.de now I did some stuff on my disk i don't want to keep and want to revert it to the snapshot point. How do I restore ...
2
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0answers
16 views

confused about dd write speed and VFS page cache

After reading some articles on the Linux VFS page cache and the tunable parameters like dirty_ratio i was under the impression that page cache would operate as both read and write caching layer. But ...
1
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1answer
49 views

LVM devices not showing in initrd but working on boot [duplicate]

I am currently working on a custom initrd based on the CentOS 6.7 (2.6) kernel with the following modules loaded. The initrd is designed to backup files off a old RHEL system into memory, unmount the ...
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0answers
49 views

IOSTAT report doesn't match with DD benchmark

I am running a DD benchmark but the obtained results are not matching with the IOSTAT values. This is the DD sample: $ sudo dd bs=4096 count=690 if=/dev/zero of=/mnt/tmp/test oflag=dsync 690+0 ...
1
vote
1answer
41 views

Wipe files from an external hard drive but not empty space

I'm using the following command to wipe an external drive. sudo shred -v -z -n 1 /dev/sdb Is it possible to wipe an external drive of the files and not empty space? So it would overwrite where ...
0
votes
1answer
42 views

GDiskDump or DD to show partition names? [duplicate]

I have partition names like Data-HD, Yhteinen and W10. I do have lots of other partitions, but I want a little more assurance I am copying a right partition to a correct destination. I am quite ...
2
votes
1answer
67 views

Taking and restoring an image of partition with dd

I created a new partition on my server /dev/sda4 with a filesystem based on ext3. I mounted the new partition /dev/sda4 on /mnt/sda4/ and created an image with dd of the partition /dev/sda3. sda3 is ...
5
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2answers
474 views

How large is the img that dd creates?

This is the first time I use the dd command. I execute: dd if=/dev/sdb2 of=/mnt/sdc1/Hdd1.img bs=512 conv=noerror,sync Where the sdb is the destroyed hdd (size: 500 GB). I copying the partition ...
0
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0answers
56 views

ARM inforce IFC6540 not booting?

I created an image of the OS on the 64GB SD card by using dd. I did something like sudo dd if=./iforgot of=/media/usb/os/os.image I can't remember the exact stuff I wrote, but I do have the os.image ...
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0answers
24 views

Is it feasible to fill a ntfs partition/device pre install with zeroess?

In my question about copying with dd one of the commentors pointed out the method of filling the unused space with 0s. Is there a way for a dd of a 80 GB hard drive to be minimal in size? Now after ...
2
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1answer
63 views

Is there a way for a dd of a 80 GB hard drive to be minimal in size?

For backup reasons I need to use dd to copy a whole hard drive (including MBR, partitions,...). The hard drive is 80 GB in size where only 1.8 GB are used. The command I'm using is the following: dd ...
0
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0answers
48 views

dd process real vs. sys time

I have two quad core workstations. One is based on Intel Atom x86_64 architecture (WS1). Another one is based on armv7l architecture (WS2). Both are running 3.10 kernel version. Identical busybox dd ...
0
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0answers
19 views

Used dd on a pen drive (wrote Arch to it with Rufus) and now it's invisible

I ran dd if=/dev/zero of=/dev/sdc count=2048 on the pen drive. I can see the pen drive in the lsusb output, and dmesg says that it is 8 GB in size, but when I use, say, cfdisk, it says that there is ...
0
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3answers
235 views

MBR size is 440 bytes or 512 bytes

I remembered reading one question how would you back up the MBR of a disk. Two of the choices are dd if=/dev/sda of=/dev/sdb bs=512 count=1 dd if=/dev/sda of=/dev/sdb bs=440 count=1 and the ...