Hi, is there a way to confirm a DD disk wipeout was successful with out using a data recovery tool?

The command I used

dd if=/dev/urandom of=/dev/sda bs=10M

Thanks and Best Regards

Read the messages when it finished.

Hi syg00, thank for the reply. I have used ILOM console to run the command and it took about 6 days to write 6TB of data. By the time I loged in next time the output has gone off the screen and I am unable to access this even with shift + pageup or down


Thanks and Regards

so save the output (= redirect it into a file)

Bit late now to save the output.
Short answer is no. /dev/urandom is really slow - I like to use /dev/zero as you can easily check what isn't zero after the fact. There are debates about the efficacy of this, but it suits me fine.

I had it, then? Only way out is to run a recovery tool!

Thank you for the input, any recovery too that you might recommend, My environment is Oracle linux 6.8, 64bit / Server HW x7-2M HD 2 x 6TB drives


Kind Regards

you can look for different recovery tools on the net (like testdisk), but that will be really slow.
rewriting (with logging, using /dev/zero) can be much faster.

Log back on the console, then hold down the shift key and press "Page Up" key...

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Nevermind, I see you have already tried this; sorry.

Could maybe use a binary editor to view the actual disk.

HI Guys, thank you for the replies,

Hi dc.901, I did try this but some how the keys are not interpreted as expected I change the Tried with different TERM values with no luck. For

and for

Hi Pan64, I have found few but looks they will take some time, was wondering of a tool that will do a quick scan and give me an out put as "no files found"

The issue is this machine was given to a customer for a POC and we need this back for another, I due to the time constrain I need this as soon as possible. Just want to know the quickest possible way to get this done.

Thank and Kind Regards

you posted it at about two days ago. All the tools would have been completed since then.

Than you for the reply Pan64

Think about what you've done. You overwrote the ENTIRE DISK with random junk...what do you expect to find when you do that? Have you thought about just plugging it in to a working system, and trying to mount it? You have no file system, no files, nothing...and if you're going to format it for reuse anyway, what's the point of this entire exercise?

I have sympathy for the OP, having been involved in a benchmark centre in a previous life. Multiple users of the same environment expected access to a clean environment. And might demand proof their data wouldn't be retrievable by the next client.
Just because a filesystem isn't mountable doesn't mean you can't scrape files off the disk(s). As I said, I like /dev/zero as you can pipe dd to hexdump and list the entire device in essentially one line if it's all zeroes. KISS.

One thing comes to mind, if this machine has a hardware RAID, then you can use the RAID utility to initialize the disks.
Then capture the output, to show as proof that disks were indeed wiped.
However, all this is depended on hardware RAID.

Otherwise, as others mentioned, next time, redirect to a file.