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Backup the first 1MB of your volume

Terminal - Backup the first 1MB of your volume
dd if=/dev/sdX of=/root/sdX.bin bs=1M count=1
2009-02-06 17:45:59
User: dhing
Functions: dd
-4
Backup the first 1MB of your volume

This will copy the first 1MB of your /dev/sdX volume to your /root/sdX.bin file, where SDX is the name of the device you wish to copy the data from (Usually a hard disk)

NOTE: Make sure you capitalize the M in field for BS.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

you should ideally set BS equal to the block size of your hard drive. this means if there are bad sectors in any given block, the copy will continue, and you will see which sector was skipped in the output. if you set bs =1M, then if there are any bad sectors the whole thing will fail.

most hard drives block sizes these days are 4096, though older ones were often 512.

Comment by quaternio 333 weeks and 4 days ago

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