Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [dd]

This command is used to do low level copying of data.

Convert and copy a file, write disk headers, boot records, create a boot floppy. dd can make an exact clone of an (unmounted) disk, this will include all blank space so the output destination must be at least as large as the input.

For more info refer to the manpage.

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where is the disk capacity stored?

In short, if I do dd disk-to-disk (e.g. /dev/sda to /dev/sdb), is the capacity of the whole disk also copied? For example, if sda is actually 1TB and sdb 2TB, after the dd, which would a Linux system regard sdb as, 1TB or 2TB? I assume that the disk…
Stephen
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How can I transfer a dedicated bare metal server into a VM?

I have the following problem: We have a dedicated (bare metal) hardware server (Debian 10) on which we have no direct physical access. Now I want to transfer all data and applications that are on this server to a VM and run it on a KVM host. Why do…
manifestor
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How to read binary contents of free disk space in CentOS

Is there a way I can use dd or another tool to view the binary contents of free disk space in CentOS? In case it matters, it's a Linux logical volume with XFS format, holding data only (not a common system volume such as / or /var). Some process…
frazierjason
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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 backup must be saved on the remote server. For do this…
Payedimaunt
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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 started running dd if=/dev/urandom of=/dev/sda bs=1M.…
user630702
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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 reduce this machine to 30 GB. I am looking for a…
Lucas
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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 into the device. Also the ethernet port could be…
Gabriel Llorens Valles
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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 whether there is a different tool-related…
theo
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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 everything copied onto the new hard drive. I've…
Ponyboy47
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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 disks in raid 1+0. Is the problem that I used bs=1G…
Sandra
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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), I get an error from dd "No space left on…
Erick
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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 the SSD size. I am now piping the dd process…
user463133
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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 a set up of Ubuntu 17.10 with mdadm and 16 SATA…
Matt Dunne
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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-three pass copy, first doing a no-split logged…
Scott
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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, /boot, /var, and so…
Brando__
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