topic Re: How to destroy data on disk in Operating System - OpenVMS

How to destroy data on disk

Guillou_2 — Wed, 01 Jun 2005 08:30:20 GMT

Hi all,

I would like to know what methods I can use to destroy data on RA92 disks before stopping a vax 6000?

Thanks for your help

regards

Steph

Re: How to destroy data on disk

Volker Halle — Wed, 01 Jun 2005 08:45:05 GMT

Steph,

INIT/ERASE device:

This will overwrite every block of the disk with the system-specified erase pattern.

Volker.

Re: How to destroy data on disk

comarow — Wed, 01 Jun 2005 15:18:45 GMT

It should be noted that the $init/erase will write a pattern of zeros. Old HSCs had a special program that wrote 3 patterns down as required by DIS.

A single pass for example is not impossible to recover, hence not DOD approved. For all practical purposes it is. If your security depends on it, than you must have three passes and keep track of the bad blocks.

Re: How to destroy data on disk

labadie_1 — Wed, 01 Jun 2005 16:10:49 GMT

melt down the disk
Less than that: security erase the disk.
Less than that: delete/erase all the files.
Less than that: delete the files.

People can recover a lot of data, so melt down the disks, if you have sensitive data

Re: How to destroy data on disk

Jan van den Ende — Wed, 01 Jun 2005 17:26:57 GMT

Steph,

we usually INIT/ERASE the disk,
then copy VMB.EXE to it, and in a loop appand it until DEVICE/FULL error.
After repeating that sequence again, at least we, consider it safe,

Of course, it all depends on your requirements.

Proost.

Have one on me.

jpe

Re: How to destroy data on disk

John Gillings — Thu, 02 Jun 2005 03:41:41 GMT

Steph,

RA92 drivers are very small capacity and very slow by today's standards. They're physically large, power hungry and have non-industry standard interfaces. The only reason you'd ever want to clear the data is if you want to sell or give the drives away. The chances of anyone wanting to use these drives again is very slim. Therefore your best option for destroying the data is to destroy the drives.

Note that the options given by others certainly deal with the accessible data on the drive, but they don't necessarily clear old data in failed blocks that have been replaced by the controller. Who knows if anyone might be able to recover data in those blocks. There are labs around that claim to be able to recover data up to 7 rewrites deep. So, if you really don't want anyone reading your data, go for the destruction solution.

A minute or so with a sledge hammer per drive might be very therapeutic to the operator and should sort out the data permanetly. For the truly paranoid, take the shards and burn them.

Re: How to destroy data on disk

Ian Miller. — Thu, 02 Jun 2005 04:40:13 GMT

the UK MOD used to sand blast the disk platters then put them in a furnace to be melted down (so I was told).
A power sanding tool would be fun to try. No one is going to want to buy these to reuse unless you know of a museum.

Re: How to destroy data on disk

Carl Couric — Thu, 02 Jun 2005 08:51:23 GMT

I seem to remember that if the RA92 was connected to a HSC, you could run dilx on the HSC and allow it to get at the data... Let it run long enough to go past those "7" write/rewrites and it should erase it.

Personally, pull the HDA, pull each data platter and put it in a shreader. The other way to erase the data is to put the HDA in an oven, heat for days.

My money is on a shreader... :)

Carl
http://www.carlc.com

Re: How to destroy data on disk

Joseph Huber_1 — Thu, 02 Jun 2005 10:07:23 GMT

At least the
"recover data up to 7 rewrites deep"
case is save by several runs of
$ ANALYZE/MEDIA/EXERCISE/FULL ddu:
Each run overrides 3 times with alternating patterns.

Re: How to destroy data on disk

Jeroen Hartgers_3 — Thu, 02 Jun 2005 10:12:15 GMT

If you do it init erase en after that you damage the drive with a hammer or drill a few holes in the drive noone could use it again

Re: How to destroy data on disk

Jan van den Ende — Thu, 02 Jun 2005 22:50:08 GMT

...
or maybe take it apart, take the platters to the next local charity fair, and offer a prize about 1/4 of the cost of the previous solutions to the person that causes the most damage...

Very effective, could well be your your most effective destruction, and put you on the list as a good charity donator as well!

Talking about win-win-win constructions...

Proost.

Have one on me.

jpe