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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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Does filling up disk with dd removes files securely?

I want to remove my files securely without worrying about anyone restoring them, I know I can use shred but it takes too long even with -n 1 so I thought maybe if I remove files and write on the disk using dd, filling up all available space I won't…
AL-Kateb
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Mount dd image with multiple partitions

I have created an image of a disk using dd using the command dd if=/dev/sdb of=/jobs/image.dd. The SATA drive /dev/sdb has 3 partitions on it (one NTFS, two FAT32). How do I mount the complete image with all its partitions in one go? I actually…
Luke Bibby
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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 `/dev/null': File too large 33619977+0 records…
Zogratz
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Cloning a bitlocker encrypted disk

Our company's had its laptops for just over 2 years now and they have all become slow and many of them have had their harddisks dying randomly lately. I noticed that many of my colleagues use a tilted stance for their docking stations. I suppose…
Jaap Haagmans
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Best way to clone a Linux system

I've just finished setting up a Debian system running on an embedded device. It has custom partitioning, numerous config file changes, web content, and a couple of applications compiled from source. This exact setup now needs mirroring to a dozen or…
harry
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Using dd on disks with different sector sizes

I would like to move a partition to a new drive. The old drive has a sector size of 512 bytes while the new one has a sector size of 4096 bytes. I tried doing a dd of the full disk, but that failed because the partition on the old drive was not…
pavon
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Mounting a linux image built with "dd" on Mac OSX 10.7

I recently did a ssh root@myserver "dd if=/dev/xvda " | dd of=//myimage.img as instructed by my VPS server docs at linode. I did this before to another linux system and mounted it perfectly by doing sudo mount -o loop myimage.img…
frazras
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How can I know if netcat & dd are working?

I'm running on server A (Source): dd bs=16M if=/dev/sda|bzip2 -c|nc serverB.example.net 19000 On server B (Destination): nc -l -p 19000|bzip2 -d|dd bs=16M of=/dev/sdb Do I need to see some progress somewhere? (Server's A /dev/sda is 50GB) I've…
soulSurfer2010
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LVM -> dd -> LVM?

I've 'cloned' a LVM partition using dd over ssh to a remote server(emergency backup...). On that remote server, is it possible to 'transform' the dd cloned file back into a LVM partition? Thanks. PS: I can access the filesystem on the cloned file,…
Mihai B.
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Best way to copy large amount of data between partitions

I'm looking to transfer data across 2 lv of an HP-UX server. I have a couple of those transfers to do, some of which are mostly binary (Oracle tablespace...) and some others are more text files (logs...). Used data size of the volumes is between…
skinp
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Does it involve network to copy a file within a NFS share?

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 asynchronously copied to memory of the NFS client which…
GP92
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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 server. In any case, I performed a DD test and am…
FriendlyBystander
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Make a dd image restorable to a smaller drive

Suppose I have a 32 GB USB flash drive (UFD) and an 8 GB UFD. I have a 5 GB partition at the start of the bigger UFD, and the rest is unallocated. The problem is to copy the partition and boot sector to the 8 GB UFD using dd or a similar tool. Is…
Hameer Abbasi
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Cloning LVM partitions

I need to clone a CentOS installation from a 1TB disk partitioned with LVM, to several identical machines. The disk is mostly empty since only the operating system and some software are installed and configured. Without LVM I would copy the entire…
Manuel
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Experiences with using `dd` to copy multi-partition, multi-FS device

I have a disc with several partitions on, each of which has a different kind of file system (ext3, ext4, and, let's say, NTFS). I want to know if I can copy the whole disc to a new one (which is of larger capacity) using dd, preferably in a single…
MadHatter
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