Questions tagged [dd]
This command is used to do low level copying of data.
180
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19 views
how to mount an dd image of a raid (file exists)
I have created a hdd image using sudo dd if=/dev/md0p1 of=/media/kic/usbdisk/hdd.img. after the backup is done, I try to mount the file for a quick check. but sudo mount hdd.img /mnt/image fails with "...
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0answers
16 views
DD copy fails because output device path change during copy
I'm trying to copy an external USB hard drive to another using DD.
my command:
dd if=/dev/sdb of=/dev/sdc conv=noerror,notrunc iflag=noatime status=progress
I'm using a live debian 10 distro.
...
0
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0answers
33 views
Migrate a VM from atlantic.net to AWS
I have a number of servers on cloud.atlantic.net put up many years ago, and now we have most of our stuff on AWS. The nice thing about AWS is it allows me to shut down (and not pay for) a rarely used ...
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0answers
25 views
How to downsize partition and remove software RAID0 without lossing data
I have Fedora 26 Linux virtual machine under XenServer with 2 virtual disks, capacity is 2x 2TB. Under Linux, there are software RAID0 and in OS is 4TB capacity. Now I do not need 4 TB and need to ...
0
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1answer
78 views
How to compress and split a backup on a remote ftp server avoiding empty space and using dd
The case is the following:
we have two servers, a remote server with ONLY an FTP access, and a local server linux where we have to configure a script for backup all system using dd command. The ...
0
votes
1answer
132 views
DD command to destroy data
Should I delete the important files of the disk and then boot into live disk and run dd command or is it okay to run dd on /dev/sda without having to delete?
I'm asking this because I've already ...
1
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0answers
20 views
DD data of drive to new drive within VM
I inherited a CentOS 7 vm with a messy disk system. Here's a breakdown:
The VM has 2 hard disks, and the OS has two LVs with luks-encryption on top. Output from lsblk:
NAME ...
0
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0answers
368 views
Reduce Volume AWS EBS EC2 LVM Partition
Problem
I have a physical machine with 1 TB disk and it was copied via command line dd, the disk was imported into S3 and successfully converted to AMI. But now I have a cost problem and I need to ...
0
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0answers
25 views
How can I automate the installation of an Ubuntu image using a USB device?
I have to automate the installation of a Linux image. The perfect behavior would be that I plug the USB, turn on the device and it runs the dd command in order to flash the image stored in the USB ...
1
vote
2answers
70 views
how can I sync 2 almost identical disk after dd
Lets say I have /dev/sda and /dev/sdb.
Before, I run dd if=/dev/sda of=/dev/sdb bs=128M, and it succeeded.
Then after some time, there is update on first disk, and I want to clone it to second disk....
0
votes
1answer
85 views
The most efficient way to save LVM snapshot to a file
I have a tricky problem with a backup strategy. The problem is with disk performance and so far I cannot do a lot about it (as well as meddle with, let's call it, pipeline design), so I was wondering ...
0
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2answers
202 views
Copy LVM Volume Group to a new single hard disk
I have a headless Ubuntu (18.04) server with 3 hard drives each partitioned to a single lvm volume group for a combined size of 6Tb. I recently purchased a new hard drive that is 8Tb and I want to get ...
1
vote
1answer
232 views
Recovering deleted plain text (emails) files from raw disk image
I'm hosting my own linux mail server for my family. Yesterday my father lost all the mails in his Inbox folder. I'm still not sure whether it's due to a terrible user error or compromised password, ...
3
votes
2answers
419 views
Unable to mount cloned partition via ddrescue
I have a problem with mounting the cloned partition. To clone it, I used as root:
ddrescue -f -n /dev/sda3 ./sda3_rescue.img ./rescue.log
The partition which I cloned, was a broken NTFS partition. ...
0
votes
2answers
139 views
Why does dd make the host unresponsive?
As root I yesterday did
dd if=/dev/zero of=/var/lib/libvirt/images/dat.img bs=1G count=1000
and for many hours it made the server completely unresponsive.
The raid controller is an HP P410 with 4 ...
2
votes
2answers
117 views
Bad Sector on disk causes the whole server to crash
Our dedicated server's hard disk was recently diagnosed with bad-sectors, and each time certain data on the disk are about to get accessed, the whole server goes non-responding before i i issue a ...
0
votes
1answer
402 views
dd “no space left on device” cloning SSD to USB drive
So I have a weird error, while dd'ing partition 3 (partition table below) from my laptop's SSD to a larger USB drive with an identical partition table. After writing ~3-4GB (expecting to write >75GB), ...
0
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1answer
4k views
HDD cloning with dd
I'm cloning a larger HDD(750GB) to a smaller SSD(250GB). I shrunk the partitions and there is only 83gb of used space. (I defragmented and did a chkdsk). Also, sum of partition sizes is smaller than ...
1
vote
1answer
776 views
Is it faster to wipe out multiple hard disks with dd=/dev/zero simultaneously?
I have 3 hard disks 1T each. I want to wipe them out completely. I decided yo use dd like so:
dd if=/dev/zero of=/dev/sdb bs=1M
dd if=/dev/zero of=/dev/sdc bs=1M
dd if=/dev/zero of=/dev/sdd bs=1M
...
0
votes
2answers
308 views
Cloning multiple SATA drives using dd with the assistance of software RAID1
So, I clone lots of Windows-based NTFS drives from images each day and I'm halfway through a project that could potentially help me and others to speed up this process dramatically.
I currently have ...
1
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1answer
146 views
Find out exact location of GRUB / GRUB not working after copying disk image
I prepared an Ubuntu server image with VirtualBox. To transfer the image to the server's SSD I first dded the MBR (512 bytes) and then the LVM partition (PV containing the root partition shrunk to 3GB)...
1
vote
1answer
387 views
Initramfs error after image restore using dd
I need to create backups of a Ubuntu system in a way that I can easily restore the data and system as it is exactly in a ready to go state. So, I decided to go with dd to create a whole HHD images.
I ...
0
votes
1answer
129 views
dmesg errors not showing in ddrescue
We had a disk in a raid go bad and we are suspicious another one might have minor errors. So to be safe we are trying to recover both disks using ddrescue. The various help pages recommend a two-to-...
1
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1answer
896 views
dd using all memory and swap
I have a dedicated Centos 6.9 linux server with a company that crashed due to hardware failure and has been restored with the old HDD's on a usb caddy. I am trying to move lvm partitions over to the ...
0
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1answer
400 views
dd's relation with page cache
The free command output of my server is currently like below:
# free -m
total used free shared buffers cached
Mem: 995 780 205 0 ...
0
votes
1answer
168 views
writing zfs dataset to block storage
Is there a proper way of writing a ZFS dataset, in my case which is an ext4 ubuntu filesystem, to a blank SSD?
The data looks like this is that's at all helpful
tank/filesystems/ubuntu_1604/(/etc, /...
0
votes
2answers
153 views
DD File Not Updating
I am following this thread to guide me from FreeNas VirtualBox to bhyve.
https://blog.yuo.be/2017/01/04/migrating-a-vm-from-virtualbox-to-iohyve-bhyve-on-freenas-9-10/
However, I am stuck with this ...
0
votes
1answer
3k views
using dd with conv=sparse to punch zeros
I am attempting to clone a disk partition to an image file using dd. I want to create the image without zeros to minimize the filesize, and on the other hand I do not want to pipe through gzip. The ...
2
votes
1answer
7k views
PXE booting .IMG and .DD images
I have read many forum posts but still can't PXE boot image files.
usb-image.dd is my image file. Instead of using USB sticks I would like to boot live Linux by using PXE.
DEFAULT menu.c32
PROMPT 0
...
2
votes
2answers
3k views
Backup and Restore Using dd and gzip
I've seen various posts discussing the use of dd for creating an image of a drive and only storing 'used data'. Before posing the problem/question, let's assume a few things.
Assumptions
The drive ...
0
votes
2answers
2k views
clone nvme drive with 4096 sector size to ssd with 512 sector size
I have an nvme drive with a logical and physical sector size of 4096.
The block size of this drive as reported by blockdev --getbsz command to be 4096 as well.
The destination drive is an SSD with a ...
0
votes
1answer
2k views
How to create a full backup of a remote ubuntu 16.04 server?
I just finished configuring a dedicated remote ubuntu server and want to create a backup with DD in order to be able to rebuild fast in case of hardware issues.
The system has 2 SSD drives with 500GB ...
0
votes
1answer
860 views
Is it possible to clone raid member disks in an array with dd
I'm looking to expand the capacity of my qnap NAS by tripling the drive size from 2TBx8 to 6TBx8. However, I'm afraid the raid 5 will die before I can rebuild the array 8 times!!
Can I remove and ...
0
votes
1answer
102 views
Two identical servers. One with extremely poor performance
I have these two servers with the following specs:
OS: RHEL 6.3 Hardware: Dell PowerEdge R610, 12 cores, 64GB RAM Drives: 6 x Samsung 840 Pro SSD RAID controller: Intel RS25AB080, 1GB Cache RAID ...
1
vote
1answer
4k views
Repair FAT filesystem on image
I've got a USB pen drive with a corrupted FAT filesystem. Now I try to repair it. So to first try what I can get from it without endangering the original hardware further, I've created an image with ...
4
votes
2answers
2k views
Does it involve network to copy a file within a NFS share? [closed]
I am assuming the following ways to copy a file with in a NFS share:
Process 1:
The client requests for the data to be copied from NFS share (if cache is not there) and the chunks of data are ...
2
votes
1answer
469 views
how to intentionally damage linux MBR (RHEL 7) on disk for test purpose?
I am running tests for MBR recovery on Red Hat Linux 7.
I tried to intentionally erase the MBR with:
dd if=/dev/random of=/dev/sda bs=1 count=512
I can see with
fdisk -l /dev/sda
that the ...
0
votes
1answer
366 views
How to use dd to dump an image to unallocated space
I have a bin file (chromiumos_image.bin) which contains some (around 12) partitions, which I need to dump into the unallocated space between 2 other partitions. The partition table is this:
My ...
0
votes
3answers
900 views
How to mount the dd image of a swap file
I have several dd images from a single drive. One of them is the swap. I mounted all of the images in Ubuntu just fine except for the image of the swap. This is how the dd images break down: hda8 is /,...
1
vote
1answer
768 views
Installing CentOS on HP Server, SSDs connected to a RAID controller
I am trying to install centOS 6.0 in this
HP Server, I contacted with the support and they said me that it supports that OS.
I have no problem installing it on a SSD that is connected directly to ...
2
votes
1answer
6k views
dd: zero-out all the remaining unused space of a drive
In the second answer of this question about disk cloning with 'dd', I read this command:
dd if=/dev/zero of=/mnt/hdb/zero
It is supposed to write '0' in the unused space of drive 'hdb', however I ...
-2
votes
1answer
298 views
Using DD to produce an Image results in empty image [closed]
I am trying to take an image of my Android phone. Specifically I have tried to image the system and boot partitions. The imaging process appears to work correctly when using dd. However, when I ...
0
votes
0answers
677 views
Shrinking an img file that contains linux partitions
I've got an img file (4,02GB) containing a Linux OS.
My goal is to shrink this img filed down to < 4GB. The img contains a linux partition that only holds about 2,5GB of data.
I need to be able to ...
0
votes
1answer
707 views
Segmentation fault on dd command
I ran this command on Ubuntu to resize the /tmp and after that there is segmentation fault coming.
dd if=/dev/zero of=/dev/xvda1 bs=1024M count=2
Its our live server. Is there any way to get it ...
5
votes
2answers
2k views
Acceptable I/O speeds for 6 x 250GB SSDs in RAID 10
I'm running CentOS 7 (XFS filesystem) on a dell server with a PERC H700 raid controller. Inside this server I have 6 x Samsung 850 Evo 250GB SSDs (yes they are consumer drives however, this is a home ...
0
votes
1answer
50 views
Backup old disk to external disk (new)
One of the 2 x 500GB drives on server is crashed can read but not write the data, which both are on Hardware RAID 0. So I connected an external 1TB new drive to backup the data and replace those 2 x ...
7
votes
1answer
458 views
File is too big for /dev/null
While testing a problem LUN for read errors, I encountered the following problem:
find /mnt/problem_lun/ -type f -print -exec dd if={} of=/dev/null bs=8k \;
...
/mnt/problem_lun/a_file
dd: writing `/...
1
vote
3answers
3k views
Truncate empy space from a raw dd image
I have a raw disk image I took using dd of a Ubuntu instance. The total disk size is 300 GB, but only 5.5 GB used.
Is there a way to resize the raw dd image down to 20 GB, keeping all of the 5.5 GB ...
0
votes
2answers
4k views
How to execute bash script through pxe boot [closed]
Can any one tell me how to execute bash scripts via pxe boot. What I am trying to do is when Raw Server boots up I want to deploy cloned image over hard disk via PXE boot.
I am aware that there are ...
-2
votes
1answer
2k views
Create random file with openssl [closed]
So I read this questionUrandom Alternative, but I am unable to make a comment there (without 50 rep) - therefore I open a separate question:
If I use this command instead of dd and urandom, how do I ...
