1
vote
2answers
63 views

live dd over a mounted read-only root partiton

I'm trying to conceive a firmware update mechanism for a Linux-based embedded system without an additional initrd/initramfs/whatever. From within the running system which has a read-only mounted root ...
-1
votes
2answers
49 views

How to unpack dd file on Windows? [closed]

Is it possible to unpack files created with linux dd tool on Windows? I have tried that tool http://www.chrysocome.net/dd, but it crashes under Windows 7. Any ideas?
2
votes
2answers
138 views

How to backup a running system?

I have a running Linux system, and I'd like to have a full backup of it using dd, which, in my limited knowledge is the only tool every system has. The distro doesn't matter mainly because I should ...
3
votes
1answer
165 views

Attempt to test corruption of ZFS filesystem using dd fails

I'm trying to test error detection and recovery on a system with recently installed ZFS. I deliberately overwrite the start of one of the disks with dd but can't force any errors to be detected. Can ...
4
votes
2answers
408 views

How to take sha-1, sha-256 or MD5 of CDs / DVDs?

I just tried burning both a Debian CD and a Debian DVD from their .iso files and I've got a weird behavior: the checksum of the CD is correct but the one of the DVD ain't. Here's what working: ...
3
votes
3answers
2k views

Force dd not to cache or not to read from cache

I'm working on an embedded system with the busybox version of dd. I'm trying to test an erase to the drive from some outside utility, however dd does not read from the disc again after the erase, but ...
3
votes
2answers
278 views

How do I refresh the magnetic state on a disks with backups?

I have a couple of large disks with backup/archive material on them. They're ext4. Regarding the ones of those that will be stored for a couple of years without reading the whole disc again I've been ...
7
votes
4answers
287 views

Protecting Devices from dd and fdisk Commands

I'm wondering if there is some way to prevent certain certain devices from becoming the output file of the dd command and the target of the fdisk command. I'm currently using the two operations to set ...
2
votes
1answer
766 views

Copying a working Linux instead of installing a new one [duplicate]

It is possible to move an installed Linux from one drive to another or from one disk to another by two methods: dd command which copies sector by sector including boot sector cp command, and then ...
3
votes
2answers
360 views

how to create ISO and hide certain files

I am a newbie here and my apologies if I am posting a question which has been answered many times in a another thread. I did my homework find some relevant information But could not. Thanks for ...
1
vote
1answer
250 views

Stripping null byte blocks with a sparse file?

I've created a sparse file with dd. How do I copy contents of another file there, leaving all the zero blocks unallocated?
6
votes
1answer
2k views

dd: writing '/dev/null': No space left on device

I am reading a 550MB file into /dev/null and I am getting dd: writing '/dev/null': No space left on device I was surprised. I thought /dev/null is a black hole where you can send as much as you ...
3
votes
3answers
448 views

from a sparse file to a block device over the network

If I have a sparse file representing a block device, then how can I efficiently restore the file over a network? Ideally, I'd use rsync -S host:file /dev/sdb, but rsync won't write to block devices. ...
4
votes
1answer
1k views

How do I create a USB image with a partition table?

I want to create an image of some directory tree that is writable directly to an USB drive, just like the images of many linux distributions. For example, with openSUSE you can download an ISO image ...
6
votes
2answers
6k views

gzip - redirection or piping?

I will be backing up a large (750GB) disk to an external USB disk using dd. Should I be using redirection or piping? Which is more efficient? Or is there a difference? Also, what is the best block ...
1
vote
2answers
2k views

How to write a file at various offsets to a filesystem partition with dd command

Requirement I want to write a file at various offsets into the partition Partition /dev/part2 is mounted at /mypart I tried the command below: dd if=/dev/urandom of=/mypart/aaa bs=1024 seek=0 ...
0
votes
3answers
215 views

What happened to my ext3 partition

I had an ext3 partition. I ran a dd command like this: dd if=/dev/urandom of=/dev/part2 bs=1024 count=15000 seek="various values" Where various values are basically 0, 15000K, 30000K etc. The ...
17
votes
3answers
4k views

Why does dd from /dev/random give different file sizes?

I am running the following command on an ubuntu system: dd if=/dev/random of=rand bs=1K count=2 However, every time I run it, I end up with a file of a different size. Why is this? How can I ...
1
vote
2answers
409 views

Embedded device: How to do raw reads and write to flash (emmc/movinand) bypassing file system cache

I have an embedded device with a flash memory running linux. I want to do raw read writes on the flash part but I also want to avoid any file system cache. How can I do this? Any pointers?
3
votes
3answers
366 views

Some basic questions about dd

I'm working on a system of how to back up partitions using dd and have been reading a lot about it. I have a few questions and assumptions that I would like to ask. These may seem a little noob-ish, ...
5
votes
2answers
1k views

Red Hat cannot boot after clone with dd

I used dd to clone a x4100 server with Linux Red Hat. The hardware is identical for old and new servers. Disks are sda, sdb and sdc(sdc1 and sdc2). But newly restored server gives following errors and ...
5
votes
3answers
5k views

How can I make a bootable usb flashdrive?

Can I just dd an Ubuntu 11.04 mini.iso to an usb flashdrive an boot from it? or what am I missing?