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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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Anyone tried dd'ing Raidmembers?

I want replace all disks in a 10 disk raid6 (linux software raid). I could do this by pulling a disk, let the array rebuild, rinse, repeat. But this would take a very long time, and cause 10 rebuilds, which would most likely stress all 10 disks much…
DusteD
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Why does dd show slow disk speed first time?

I'm checking the disk speed of a hdd on CentOS 6 using dd command. The setup is a DRBD setup - with this server being primary. To ensure that I get correct values, I execute the dd command 3 times with different output files and then take average of…
amolkul
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Use dd or redirection to write to tape?

My Googling for writing to tapes with encryption have turned up various results. Most along the lines of piping tar to openssl similar to: tar cf - /home | openssl des3 -salt -k "Your-Password-Here" Some then pipe to dd, while other just redirect…
fukawi2
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How to move partitions from 2 LVM volumes into one LVM on other disk?

i had 2 partitions with following layout Disk /dev/xvda: 376.4 GB, 376354897920 bytes 255 heads, 63 sectors/track, 45755 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size…
Farhan
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DD broke my whole partition - boot failed: not a bootable disk . Any way to recover it?

Im kind of freaking out here, if anyone can help me please help me... This happened to a Windows 2012 KVM virtual machine. I had a very important database running in it, if I could only recover that DB it would be great. The VM was struggling…
viniciusmunich - AssabetTech
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Differences between hdparm --read-sector and dd with "Current Pending Sectors"

This was originally an "answer" to How to use hdparm to fix a pending sector? I'd been getting SMART notifications for the same "Current Pending Sector" for days. The dd solutions around weren't resolving anything (they'd appear to zero data and…
bsb
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Why is my synchronized I/O so bad compared to direct?

I have two 3TB disks in a software RAID 1 setup and the host OS is 64bit Debian wheezy. Issuing: dd if=/dev/zero of=test bs=64k count=3k oflag=direct && rm test Yields: 201326592 bytes (201 MB) copied, 1.423 s, 141 MB/s If I alter the dd command…
corford
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Server crash when creating a swapfile on a running machine (CentOS Linux)

I created a swap file with root on a running server, using swapfile creation guides which I found on the net (http://blog.serverbuddies.com/adding-additional-swap-space-to-your-linux-server/m Create swap file on a running Linux machine, and…
giorgio79
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Operating System not found when loading DD image in VMware

I provide much details below to hopefully make my issue as clear as possible. Using dd if=/dev/ps3da2 of=/mnt/edexhdd/EDPS3LINUX.iso bs=16384 I copied a fairly huge partition from a physical Linux non-Xwindow installation on a PPC64 architecture…
EdNdee
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dd and drive imaging

When you image a drive with dd, you get a image usually of the same exact size of the drive. You can compress the image, but that is really Dependant on how many continuous null's or zeros their are on the drive. My question is, does another tool…
Recursion
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Heavy disk write on a Debian VPS gives "ata1: lost interrupt (Status 0x50)"

I have a new Debian VPS that appears to fail almost every time I run a heavy disk write test on ext4 filesystem. The filesystem goes to read-only mode and "ata1: lost interrupt (Status 0x50)" is recorded to /var/log/messages. What do you suggest me…
XDF
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How to delete the MBR (Master boot record) out of an image file?

I have a QEMU image myserver.img that is about 20GiB. The file serves as a "virtual" hard disk for the server. Now the first 512 bytes contain the MBR, and I am trying to overwrite those bytes with zeroes. On a normal disks, this one would work: dd…
Daniel
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linux dd software raid?

Please advise what is the best way to create linux software raid image with dd? /dev/md0 consists of /dev/sda & /dev/sdb. I ran dd if=/dev/sda of=sda.img same for sdb Restored on the remote system Restored MBR Now I'm getting some error that could…
RomanG
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Clone hard drive Solaris 8 (SunOS 5.8)

I have an old 73gb SAS SCSI drive, so I plugged in a new 73gb SAS SCSI and I want to clone everything from it to the new drive.. I want to clone SCSI hard drive SD20 to SD21. Is there an easy way to accomplish this in Solaris? I am a Red Hat Linux…
IT_Fixr
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Disk cloning using dd thru gzip - how effective is it?

Is gzip or gzip -9 for a disk clone worth the extra time that it takes to perform the compression? Does it yield a significant saving? There is very little information on how effective piping data from dd thru gzip really is. (Some data simply…
thinice
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