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

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17
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3answers
2k views

Securely wipe an entire Linux server with itself

I have remote ssh access and root access. I do not have physical access. I'm not looking for solutions involving booting into anything, I want to do this from what is currently running. OS is SL6. ...
3
votes
2answers
386 views

Save data after accidental dd format

as embarrassing as it sounds I managed to dd a debian iso to an external hd instead of my usb pen drive. now my 1.5 tb western digital has 1 700mb partition named debian and the rest is unallocated ...
1
vote
0answers
487 views

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 ...
0
votes
2answers
779 views

Clone Flash Drive in Linux using DD

dd if=/dev/sda of=/dev/sdb I want to create a clone a bootable USB stick. lets say sda is 2GB sdb is 32GB. The above line will create a replica but the usable size will be 2GB. How can I use the ...
2
votes
1answer
1k views

dd oflag=direct 5x fast

I have Centos 6.2 in server with this specs: 2xCPU 16 Core AMD Opteron 6282 SE 64GB RAM Raid controller H700 1GB cache NV - 2HD 74GB SAS 15Krpm RAID1 stripe 16k (OS Centos 6.2) sda - 4HD 146GB SAS ...
1
vote
2answers
172 views

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 ...
2
votes
3answers
95 views

Backup with dd upon reboot

I'm trying to implement the easy to maintain backup solution for our local linux server. The goal is to be able to restore the whole system from image file. What I am thinking of is just to issue ...
1
vote
1answer
640 views

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 ...
8
votes
2answers
1k views

How can I split a drive image created with 'dd' into separate files for each partition?

I created an image of a failing drive with: dd if=/dev/sde of=/mnt/image001.dd The drive had only two partitions: Device Boot Start End Blocks Id System /dev/sde1 * ...
4
votes
3answers
6k views

Moving a Logical Volume directly from one server to another over the network?

I have a KVM host machine with several VMs on it. Each VM uses a Logical Volume on the host. I need to copy the LVs to another host machine. Normally, I would use something like: dd ...
1
vote
2answers
1k views

Partition size inconsistency after dd clone

We have recently upgraded a system HDD - it was 160GB, now 2TB. We upgraded as we were running low on space, mainly on /usr, and also on /home. I prepared the new drive with a Live CD and GParted ...
3
votes
2answers
203 views

How to view a full disk data (more than one partition) cloned with dd

I've a disk image done with dd: dd if=/dev/sda of=/mnt/fulldisk.img /dev/sda have some partitions (Windows+Linux) My problem is: I need to know if the image is done well, how can I access data? ...
3
votes
2answers
799 views

In Linux, how can I create thin-provisioned file so it can be mounted and a filesystem created on it?

I am building a system that gives users certain amounts of disk space. The way I am doing it is: create a file with dd create an ext4 filesystem inside the file mount the file and tell the user ...
1
vote
1answer
830 views

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 ...
-1
votes
1answer
81 views

How does this benchmark calculation work?

I am testing disk I/O performance on a server of mine, which will eventually run Postgresql. I am following this web site to perform my benchmarks. The benchmark consists of running dd and ...
1
vote
2answers
284 views

Disk cloning using dd thru gzip - how effective is it? [closed]

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 ...
1
vote
2answers
464 views

Large delay starting “dd” write in background in bash even when using nohup

I wrote a small script to print the memory usage during a large sequential write of a file. #!/bin/bash rm result echo 3 > /proc/sys/vm/drop_caches sync; echo start nohup time dd if=/dev/zero ...
2
votes
1answer
866 views

Raw copy with sector precision on windows

Is there some program for windows that is able to do what dd does in linux out of the box? I need to copy from a file to a physical disk in raw mode where I need to define offsets for input and ...
6
votes
2answers
3k views

/dev/zero equivalent in windows?

I am trying to use the windows version of dd to copy a RHEL iso to a USB stick. However, I wanted to zero out the drive first to ensure there is no filesystem on it before writing it out. Is there an ...
1
vote
1answer
96 views

Cloning a two partition HDD onto a smaller HDD and maintaining MBR

I have a hard disk(A) containing two partitions - A1 is a NTFS partition containing a windows OS, and A2 is an NTFS partition containing data. I want to copy both of these partitions onto a different, ...
0
votes
1answer
276 views

Oracle 10g cannot start after cloning server with dd

I used dd to clone a x4100 server with Linux Red Hat. The hardware is identical for old and new servers. Then I changed IP address and host name. The newly restored server is up and running but Oracle ...
0
votes
1answer
226 views

LVM tools on raw block copy

I have several raw block copies of disks that have both NTFS and Linux partitions. The parition tables generally have both a Windows NTFS partition and a Linux LVM partition. I need to work on all of ...
0
votes
1answer
633 views

Writing with dd in an NFS mount point

I am trying the following: sudo dd if=/dev/sda1 of=/mnt/nfs/l bs=1M It fails: dd: opening `/mnt/nfs/l': Permission denied However, normal file creation and writing with "cat" works. What could ...
0
votes
2answers
209 views

copy boot-able partition

I have an disk image with 3 partitions: first partition (hd0,0) is boot-able with GRUB1 with the following configuration GRUB file: default=0 timeout=5 title Bank A root (hd0,1) ...
0
votes
1answer
120 views

Does writing many times to a HDD cause early failiure

How many times could i run something like dd if=/dev/urandom/ of=/dev/sda before the hdd starts to suffer? I thought in a modern hard drive the head doesn't touch the platter, but i am still not ...
0
votes
1answer
456 views

sfdisk - partition creation problem

I'm trying to create disk image with 2 partitions: First partition: 1Mb for boot and second partition of the maximum capacity dd if=/dev/zero of=flash.img bs=1M count=10 /sbin/sfdisk flash.img ...
6
votes
1answer
2k views

combine partitions to one disk image

I have 3 images. Each image was done by cloning (by dd) a partition (these partitions formatted using ext3 file system). One partition is boot-able with GRUB1 (CentOS) How can I combine them to one ...
0
votes
2answers
375 views

How to clone with cat?

I want to clone an 8.1gig bootable disk to an 8.0gig disk and have the clone remain bootable. dd causes problems because the destination disk is a few mb smaller than the source. Can "cat" help me ...
2
votes
2answers
2k views

Monitor Disk I/O Using DD

I've bee looking into the possibility that my server is experiencing a lot of iowait issues. I've found a lot online about running the dd command. I am unable to run this conv: [root@vps ~]# dd ...
2
votes
2answers
3k views

Is it possible to restore disk image to a different size hard disk

recently I made a backup 120 GB disk image using dd: dd if=/dev/sda of=backup.img Now I have a new 320 GB hard disk and want to restore that backup image to that new disk. Will running dd ...
2
votes
2answers
497 views

After using dd new disk cannot be booted and partition tables lost

After I used dd to clone a 120 gb hard disk to new empty 320 gb hard disk, the new disk cannot be booted. And fdisk tell me the partition table is no valid and Gparted just cannot edit the ...
0
votes
1answer
257 views

Clone a real server to a VPS

I have an old server ( Red Hat Enterprise Linux ES release 2.1 (Panama) ) that is in desperate need of replacing, is it possible using dd / ssh to clone the server onto a Rackspace VPS? Or more ...
0
votes
3answers
729 views

SME Server: How do I do nightly Ghost-like backups?

I need to drop another hard drive into my company's SME Server-powered fileserver and figure out a way to do a nightly clone backup of the entire filesystem so that, if the hard drive fails, I can ...
1
vote
2answers
125 views

Copy a partition into a new image out of an existing dd image

How can I dd an image of a single partition out of a full-disk image? I know skip and count, but I am supposed to divide by bs, and since this is the first partition, it's start point is early in the ...
4
votes
6answers
2k views

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 ...
4
votes
4answers
419 views

IDE compatability with SATA image

We had an old CNC machine's hard-drive fail recently. The hard-drive is an old 1275MB IDE (Seagate) and there were defiantly bad sectors on it. I was able to image the contents of the drive onto a ...
0
votes
3answers
270 views

Is it possible (and how if it is) dump two concatenaded disks in a new disk using DD?

I have a Lacie enclosure that has a setup with 2 500gb disks configured as 1 drive of 1TB, the only partition created for the whole drive is HFS+ journaled, but the controller in the enclosure is gone ...
0
votes
2answers
581 views

CentOS 5.5 installation on disk image

Today, in order to install CentOS 5.5 I'm using kickstart script. I would like to install CentOS on different way: Create disk image (using dd command) Create filesystem on this disk image using ...
0
votes
1answer
900 views

Clone disk with dd, and change blocksize?

I need to clone my 300GB disk to 500GB disk with dd, but the old disk (300GB) has too *big block size. Will this change the block size of output partition too? I understod that obs only meant to be ...
1
vote
3answers
1k views

Extracting Data from Raw Hard Drive Copy?

A while back something happened to my hard drive that wiped out the partition table and left my data unreadable. I had other uses for the drive, but I didn't want to give up on trying to recover the ...
0
votes
1answer
474 views

dd cloned win2003 std ntfs partition, “no operating system found”

I cloned an existing ntfs partition on faulty hardware using dd and gzip. The copied partition was then written to a newly created ntfs partition on a new disk (on another server) and the bootable ...
4
votes
3answers
1k views

Get exact size in bytes of a disk & partitions in windows

I'm using dd (under cygwin) to copy a shadow image of a disk in windows. Shadow copy will only give me a partion, so what I am doing is: 1) using dd to grab the disk header (32k on Win2003) 2) using ...
4
votes
2answers
6k views

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. ...
0
votes
4answers
432 views

Why dd finishes instantly when pipelining to cat?

I start bash on Cygwin and type: dd if=/dev/zero | cat /dev/null It finishes instantly. When I type: dd if=/dev/zero > /dev/null it runs as expected and I can issue killall -USR1 dd to see ...
4
votes
3answers
2k views

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 ...
2
votes
5answers
3k views

Creating a 80GB image with dd on a FAT32 drive

I have a question concerning the creation of an drive image with dd. Normally i would simply type: "dd if=/dev/foo of=/dev/bar". But in this case i only have a fat32 formatted drive at hand, which ...
1
vote
2answers
724 views

cloning with dd - is non-partitioned space considered the same as empty space within filesystem for resulting image size?

note: all = all that i've found all the "cloning with dd" information talks about how dd copies all the "empty space", but literally all writings seem to be responding to a situation where ...
1
vote
2answers
299 views

How can I use dd to back up the whole disk from inside a linux-vserver guest?

I have a Linux-vserver guest I want to dump the whole disk of. I have no access to the host. I tried: dd if=/dev/hdv1 | gzip -c | ssh user@remote.host.net 'dd of=/path/to/file.img' bs=2048 but the ...
1
vote
1answer
570 views

zeroing a disk with dd vs Disk Utility

I'm attempting to zero a disk on my Mac OS X machine. I'm going for complete zeros and unformatted, so I think of dd. Unfortunately the maximum throughput I've managed to get out of dd is 7MB/s. ...
1
vote
4answers
1k views

Best choice for off-site backup: dd vs tar

I have two 1TB single-partition hard disks configured as RAID1, of which I would like to make an off-site backup on a third disk, which I am still to buy. The idea is to store the backup at a ...