Using Diskpart

[Bare Foot Kid]

Hello everyone.



What I would like is to do is a "secure erase" (write zeroes) to a partition of a HDD before a clean install of Windows 7. If I were to boot to a http://www.sevenforums.com/tutorials/682-command-prompt-startup.html?ltr=C would the series of commands in the snip below secure erase (zero) the partition; then I could clean install Windows 7 to that same partition.

Does a full format do a secure erase to the partition? I don't really want to use a 3rd party prog. to do it if Diskpart will.

I hope y'all understand what I'm asking.

 

[Brink]

Hello Ted,

You can use the Clean All command to "secure erase" a hard drive to completely wipe it clean.

Hope this helps,
Shawn

 

[Bare Foot Kid]

Hello Brink.

Thanks for the reply.


I've been experimenting with that and a "clean" and a "clean all" command remove the partition structure from the HDD and make it "unallocated" space and I don't want that to happen, I want to do a secure erase to a partition on a HDD with data on other partitions on the HDD and not lose that data.

 

[Brink]

While the "format" command is not as a "secure erase" as using the "Clean All" command, if you "format" and install Windows on top of it, it should pretty much wipe out any traces of data that was on the HDD.


Quick Format - only rewrites the boot record of the media and makes the whole space available for writing data. Althought physically, previous data is still present, only marked as free space.

Full Format - formats everything as well as test (dskchk) each sector for Read/Write problems. Sectors with problems are marked as bad. Since it tests every sector, depending on the hard drive size and computer speed may take many minutes or hours to do.

 

[Bare Foot Kid]

So any data on the partition would be pretty much un-recoverable after a full format and a clean install?



Thank you Shawn.

 

[Brink]

I'm sure that the government will still have a way to recover some data from it if push came to shove, but it would be practically unrecoverable for your average joe.

If you truly need it wiped cleaned, then it's either the "Clean All" command, or a 3rd party disk scrubbing program with several passes that would need to be used to do so.

 

[Bare Foot Kid]

I realized after I posted that that I was making it sound as though I have "stuff" I want hidden, I don't, I just want a clean slate when I do clean installs from now on.


Thank you very much Shawn.

I also want to say "thank you" to Jonathan_King for his help with this also.

 

[Tepid]

You don't have to be a criminal or a spy to want a truly clean drive

There is a little known command built into all modern drives firmware.....

CMRR - Secure Erase

HDDerase.exe is a DOS-based utility that securely erases "sanitizes" all data
on ATA hard disk drives in Intel architecture computers (PCs). It offers the
option to run the drive internal secure erase command, security erase unit,
based on the ATA specification by the T13 technical committee.

This does not work on USB or SCSI drives.

It has been my understanding over the years of researching that the following refers to Bad Sectors as well..

Q: What is the difference between secure erase and enhanced secure erase?

A: Secure erase overwrites all user data areas with binary zeroes. Enhanced
secure erase writes predetermined data patterns (set by the manufacturer) to
all user data areas, including sectors that are no longer in use due to
reallocation. ***NOTE: the enhanced secure erase option is not supported by
all ATA drives.

No other software or method will also erase data on bad sectors.

So even if you erase a drive of data. Any data that was written to a sector that has
been marked bad can be recovered using exotic lab techniques for data recovery.

There are many devices now that are certified and can claim full certification for
things like HIPAA and other very sensitives data erasure needs that only use the
Internal Wipe Command to completely erase all data from a drive that could be
re-used in any capacity.
Which makes the Internal Wipe Command very favorable for anyone who is about to trash,
or resell a system that they may not want sensitive data to be recovered from.

Keep in mind that this is a full disk erasure.

 

[ignatzatsonic]

Tepid:

Sounds interesting. Have you actually used this app? I have downloaded it, but gone no further.

It appears that the EXE file is actually called hdderase.exe rather than Secure Erase?

I guess you have to burn it to a bootable CDR and then boot from it.

Any issues and do you have an estimate of how long this takes to run on a 1 TB drive scheduled for disposal?

Barefoot Kid:

Here are the commands I use with Diskpart, after hitting Shift F10 during setup:

list disk (to show the ID number of the hard disk to partition, normally Disk 0)

select disk 0 (change 0 to another number if applicable)

clean

create partition primary size=80000 (create a partition with 80 GB space; to use the entire disk as one partition, omit the “size=value” parameter switch; use a similar command to create more partitions if needed or create in Windows 7 after installation)

select partition 1

active

format fs=ntfs quick

exit

 

[Brink]

Hello Ignatzatsonic,

The data on the HDD is not written over using the clean or format quick command. It is only marked as being deleted and can be written over when new data is written/saved to the HDD next. You would have to use the clean all command for a secure erase to have all the data written over with 0's on the HDD instead though.

http://www.sevenforums.com/tutorials/52129-disk-clean-clean-all-diskpart-command.html

 

[CommonTater]

Hello everyone.
What I would like is to do is a "secure erase" (write zeroes) to a partition of a HDD before a clean install of Windows 7.

Ok, having looked at the fist part of this thread, I can chip in a little information for you...

Simply this... "Format" is not "Erase"... Even a long format which can take hours to finish is only a surface scan done in READ mode, while this will map bad sectors out of the $Bitmap file in NTFS it will neither fix bad sectors nor erase any pre-existing data.

You will need a 3rd party program to "Zero fill" your drive... Google is your friend... there are lots of them.

However... If you are just doing a clean install, format is plenty good. Yes there's still going to be recoverable data on the drive but that data is neither listed in any directory nor indexed in the Bitmap or MFT records... so as far as windows is concerned it's working on a brand new disk.

The reason old data is not reset to some predetermined value is simply that it's a waste of time. If you had to write zeros on a drive before you could write new data (like they had to do with old magnetic core memory) the process would take *at least* twice as long. With a hard disk you just ignore the old stuff and write over top of it... and that's plenty good enough.

The only time I'd recommend a zero fill is if the drive is leaving your possession with "confidential" data on it... Your financials, medicals or (heaven forbid) something illegal....

 

[ignatzatsonic]

Brink:

Thanks for that clarification.

I guess a person may as well use "clean all" every time rather than "clean" for the sake of security. No harm done other than more time taken.


I gather "full format" is no more secure than "format"?

I assume "Clean all" is the only command available at a prompt in Windows 7 natively that will write zeroes and can write zeroes to C if you boot from the Windows 7 DVD?.

Do "clean all" and "full format" differ significantly in how long either would take to run on a 1 TB drive?

 

[Brink]

Nar, format doesn't actualy erase (write over) the data but just marks them as deleted instead. That's why you may sometimes be able to use a data recovery program to recover data that has been deleted or formatted if it has not been writen over yet.

The Clean all will write over all data on the HDD for a secure erase.

A "full format" (regular format) will do this instead: Differences between a Quick format and a regular format during a "clean" installation of Windows XP

I'm not sure how long it will take, but I would imagine that would take a bit for a 1TB drive to run a "clean all" on.

 

[Tepid]

Yes I have used HDDErase which is the application that calls the internal wipe command of the firmware.
There is no direct route to this command other than using hdderase, and I think a very small (like one other) number of applications that can access this command.

There are some caveates to using it, and yes, you can render a drive useless. Which I have done a couple times. But, if everything goes well, you can be assured that (again, to the best of my knowledge, from the research that I did a couple years ago) all data, including bad sectors are wiped clean.

I have not used it in a long time, but I am pretty sure this Internal Wipe Command is still on every drive sold today.

How to REALLY erase a hard drive - Update | Storage Bits | ZDNet.com

What is Secure Erase?
Secure Erase is built into all ATA-compliant disks drives since 2001. This functionality is recognized by the US Government’s National Institute of Standards and Technologies (NIST) as equivalent to magnetically wiping a drive (degaussing) or physically destroying it. NIST also rates the secure erase commands as more secure than external host-based drive wiping utilities such as Boot and Nuke. Secure Erase complies with HIPAA, Personal Information Protection and Electronic Documents Act (PIPEDA), the Gramm-Leach-Bliley Act (GLBA), and California Senate Bill 1386 for data destruction.

Doing a Zero Fill can be used and is good for the average joe that doesn't really care about wether or not data can be retrieved,but just wants to be secure in the knowledge that most people can't recover the data. Someone getting a hold of a drive that knows what they are doing could still get pieces of data from the drive. Trust me I have researched this.

There are articals out there that talk about even being able to recover data from a shredded drive. Meaning they put the drive through a shredder and grind it down. This is a bit over kill but it has been done according to articles I have read. Or at least theorized. It has been a while since I read anything on this. I did research cause a company I was working for was looking into HIPAA re-certification of HDD's used in the medical field. So they could either resell them or reuse them in other areas of the company. Trust me it is a bigger deal than you think in the medical field for HIPAA among other areas that control sensitive data.

You get hacker eddie that knows how to recover data and a zero wiped drive can give up juicy data.

It all depends on how concerned you are about the data on your drive.

i just put the Internal Wipe command info out here as just that, knowledge, to be taken and researched on further by those interested.

 

[Bare Foot Kid]

I want to thank you all for the information.