You give off your computer,or sell it.There be personal inf

[FireSoul]

Many will give up the computer and there may be personal information, that time is not enough to just formatting, or delete.
The current liinux live CD / DVD in most program that overwrite.Use the proper data extraction.
A number of companies to change computers every few years, so that they could provide equipment for further use, keep your important data permanently remove and properly.
In general, it is sufficient to write more than 3 times, I'll post an example of how it can be done.

Shred - Installation is one of the programs for that purpose made for Linus.

Many Linux distributions shred command is ready. The installation can be checked by running the console / terminal command ---> shred -- version , which prints the data used in the shred.

If necessary, the system will be installed shred coreutils package, which can be installed in your system, for example, through the package management. Many Live-CD/DVD distributions shred is standard, so it can be used directly from Live CD/DVD took place after the launch (Linux does not need to separately install the shred command to use).

Shred - User files

Single file, overwriting and deletion, follow these steps console / terminal via:
shred-u file name
for example, the home directory found naked.jpg image file to overwrite and delete the following command:
shred-u / home / user / naked.jpg


By default, shred overwrites the file 25 times. Overwrite number may be changed using the parameter n.
for example, the home directory found naked.jpg image file could overwrite 10 times and remove the command:
shred-n 10-u / home / user / naked.jpg


If you would like information on the progress of shredin, use the-v parameter.
for example, the home directory found naked.jpg image file to overwrite and delete with the command
shred-u-v / home / user / naked.jpg


Shred - Use as storage devices and partitions with

Overwriting a single disk partition, follow these steps console / terminal via:
shred-v-1, the partition
-V parameter will overwrite the progress and 1-n-parameter partition overwritten once.
for example, a second partition on the first hard disk overwriting once succeeds with the command:
shred-v-n 1 / dev/hda2


The whole mass memory overwrite in turn can run:
shred-v-1, the mass storage
-V parameter will overwrite the progress and 1-n-parameter partition overwritten once.
for example, the first hard disk overwriting once with
shred-v-n 1 / dev / hda

I do not remember seeing any posts on here, so maybe this one can be of help.

[igor83]

Many will give up the computer and there may be personal information, that time is not enough to just formatting, or delete.
The current liinux live CD / DVD in most program that overwrite.Use the proper data extraction.
A number of companies to change computers every few years, so that they could provide equipment for further use, keep your important data permanently remove and properly.
In general, it is sufficient to write more than 3 times, I'll post an example of how it can be done.

Shred - Installation is one of the programs for that purpose made for Linus.

Many Linux distributions shred command is ready. The installation can be checked by running the console / terminal command ---> shred -- version , which prints the data used in the shred.

If necessary, the system will be installed shred coreutils package, which can be installed in your system, for example, through the package management. Many Live-CD/DVD distributions shred is standard, so it can be used directly from Live CD/DVD took place after the launch (Linux does not need to separately install the shred command to use).

Shred - User files

Single file, overwriting and deletion, follow these steps console / terminal via:
shred-u file name
for example, the home directory found alaston.jpg image file to overwrite and delete the following command:
shred-u / home / user / naked.jpg


By default, shred overwrites the file 25 times. Overwrite number may be changed using the parameter n.
for example, the home directory found naked.jpg image file could overwrite 10 times and remove the command:
shred-n 10-u / home / user / naked.jpg


If you would like information on the progress of shredin, use the-v parameter.
for example, the home directory found naked.jpg image file to overwrite and delete with the command
shred-u-v / home / user / naked.jpg


Shred - Use as storage devices and partitions with

Overwriting a single disk partition, follow these steps console / terminal via:
shred-v-1, the partition
-V parameter will overwrite the progress and 1-n-parameter partition overwritten once.
for example, a second partition on the first hard disk overwriting once succeeds with the command:
shred-v-n 1 / dev/hda2


The whole mass memory overwrite in turn can run:
shred-v-1, the mass storage
-V parameter will overwrite the progress and 1-n-parameter partition overwritten once.
for example, the first hard disk overwriting once with
shred-v-n 1 / dev / hda

I do not remember seeing any posts on here, so maybe this one can be of help.

I don't like the linux utilities for erasing hard drives. I've tried some of the shredders available via Ubuntu's software manager, and they are not that great. Overwriting any file more than once is pointless. That's what shred wants to do, and it seems paranoid to me. There have been research papers published on this subject before. To overwrite every file 25x would take days on a 2tb drive. Days. You want to sit there watching your computer work day after day on some old hard drive?

Give me the Windows utility CCleaner anyday. It will overwrite all bytes on the drive as many times as desired, using an easy-to-understand GUI interface, and it is fast. I just don't trust the linux utilities for something crucial like this. Their documentation is not nearly well-written enough and the interface not refined enough to justify 100% confidence in the programmers. They didn't spend time to develop a GUI, so I'm thinking maybe they haven't worked out all the bugs in the program to start with. Maybe they're skipping some bytes here and there to speed up those 25 writes per byte. Maybe they're miscalculating. Maybe it's not writing to the disk at all.

If one does not have access to Windows, then I would recommend taking a hammer to the hard drive and hitting it many times as hard as you can. But I've sold many a used hard drive on Ebay after having it wiped clean by the Windows program CCleaner. All that is required is wipe-once, every byte on the drive. Another good method is to format the drive and then copy .mp3 files on it until it is full, then format again. Easy as 1-2-3.

[catweazel]

Shred

Great way to completely brick an SSD.

[igor83]

Shred

Great way to completely brick an SSD.

Do SSD need shred at all? I'm thinking they don't. Once a file is deleted on SSD, is it gone for good, or is there a ghost?

[FireSoul]

Shred

Great way to completely brick an SSD.

Do SSD need shred at all? I'm thinking they don't. Once a file is deleted on SSD, is it gone for good, or is there a ghost?

We know this don't need to for all computers what are used personal use and don't have any critical files,you can see there are choice to use for only parts too.
Companies can not take the risk of handing over the future use of computers.

[catweazel]

Do SSD need shred at all? I'm thinking they don't. Once a file is deleted on SSD, is it gone for good, or is there a ghost?

The only way to clear an SSD safely is to issue the ANSI T-10 Secure Erase command on the SATA bus. As for file deletion on SSDs, they are erased by marking the file as deleted. At some point in time, the marked files are filled with hexadecimal FF, which takes place only in the background and is done only at the whim of the operating system issuing TRIM commands. The filling is done to speed up disk writes, because only entire blocks can be erased, not parts of blocks. It's necessary to do it this way because an SSD is a massive array of electron traps that don't actually have a 1 or 0 setting. Instead, a certain number of electrons or above sitting in the trap is trreated as 1. Conversely, a certain number of electrons or below is considered to be 0. These traps sit in blocks and, as I said, the whole block must be erased. So, the answer to your question is no, a file is not deleted for good. At least not until the TRIM command is issued.

Unlike a normal HDD where 0 is 0, on an SSD, 0 is actually 1, hence zeroing an SSD will degrade it, and eventually it will be useful only as a doorstop or mantle ornament.

As for the paranoid rant above about privacy, the ANSI T-10 Secure Erase command can be used on any SATA device, HDD or SSD. It's quick and safe. There is a DOS application available that does it, but I haven't seen a Linux one around. It takes less than one full second to secure erase a 128GB SSD.

[Pierre]

going on the theory that most of the PCs that I get, are X_win
- just installing a 'nix O/S will effectively stop <most> people from getting to that underlying win O/S . ..
- most these PCs are poorly wiped anyway, - even by the Gov't Dept that it came from

so I'm doing the previous user - a favour by installing a 'nix O/S.

if it is a 'nix PC that you are disposing of - using Gparted to erase the partition(s) should be quite enough.
- reversing that will only yield a 'nix O/S that has a pwd - for the user(s) - that has to be cracked / changed,
- again outside of the ability of just about everybody . .

- if you data was That Critical - then use a drill to put some Hole(s) into the drive - to destroy that drive - permanently.

[igor83]

We know this don't need to for all computers what are used personal use and don't have any critical files,you can see there are choice to use for only parts too.
Companies can not take the risk of handing over the future use of computers.

I do not understand what you are saying, sorry. Perhaps you don't understand what I am saying, either. Are you using Google Translate? Sometimes it is not that accurate.

[igor83]

Do SSD need shred at all? I'm thinking they don't. Once a file is deleted on SSD, is it gone for good, or is there a ghost?

The only way to clear an SSD safely is to issue the ANSI T-10 Secure Erase command on the SATA bus. As for file deletion on SSDs, they are erased by marking the file as deleted. At some point in time, the marked files are filled with hexadecimal FF, which takes place only in the background and is done only at the whim of the operating system issuing TRIM commands. The filling is done to speed up disk writes, because only entire blocks can be erased, not parts of blocks. It's necessary to do it this way because an SSD is a massive array of electron traps that don't actually have a 1 or 0 setting. Instead, a certain number of electrons or above sitting in the trap is trreated as 1. Conversely, a certain number of electrons or below is considered to be 0. These traps sit in blocks and, as I said, the whole block must be erased. So, the answer to your question is no, a file is not deleted for good. At least not until the TRIM command is issued.

Unlike a normal HDD where 0 is 0, on an SSD, 0 is actually 1, hence zeroing an SSD will degrade it, and eventually it will be useful only as a doorstop or mantle ornament.

As for the paranoid rant above about privacy, the ANSI T-10 Secure Erase command can be used on any SATA device, HDD or SSD. It's quick and safe. There is a DOS application available that does it, but I haven't seen a Linux one around. It takes less than one full second to secure erase a 128GB SSD.

Thanks for the info on SSD. So one needs a special utility to secure-erase it,but the utility is lightning-fast. And there's no such utility in the Linux world. Are you not exaggerating in saying that zeroing an SSD will degrade it? SSD have a limited number of writes, in the tens of thousands I think? so any type of write, not just zeroing, will degrade its longevity by a very tiny amount.That is why operating systems need a bit of tweaking to dial down unnecessary writes when one is using an SSD. I'm talking about noatime in the Fstab and so on.

[meteorrock]

Just pull the RAM and hard drives. Or do a total wipe of your hard drive with these commands. Rewrite it a few times so your **** is all wiped out

WARNING TO IDIOTS. This will WIPE YOUR **** off of your comp completely.

dd if=/tmp/0 of=/dev/sda1 bs=1
dd if=/tmp/1 of=/dev/sda1 bs=1
dd if=/tmp/2 of=/dev/sda1 bs=1

/tmp/0 has 1 byte that is 0
/tmp/1 has 1 byte that is 1
/tmp/2 has 1 byte that is 2

Enjoy. If you want to be totally safe, just take a hammer to the HD and pull your RAM cards. Some hackers can pull code off of your RAM cards even with it powered down. Dont forget that cache on your router guys, I can find tons of info without even exploiting your computer at all, and just pull logs from your router.

[FireSoul]

Thanks from comments.

Good,we got good comments and some different ways.

We know most of computers are with windows as them are new,we make them to linux and so if we get some from companies.Companies want files of them are not seeing as some use later same computers.I think companies don't give most critical for anyone,but there can be something what is good to owerwrite.

[igor83]

Just pull the RAM and hard drives. Or do a total wipe of your hard drive with these commands. Rewrite it a few times so your PRONZ is all wiped out

WARNING TO IDIOTS. This will WIPE YOUR SH*T off of your comp completely.

dd if=/tmp/0 of=/dev/sda1 bs=1
dd if=/tmp/1 of=/dev/sda1 bs=1
dd if=/tmp/2 of=/dev/sda1 bs=1

/tmp/0 has 1 byte that is 0
/tmp/1 has 1 byte that is 1
/tmp/2 has 1 byte that is 2

Enjoy. If you want to be totally safe, just take a hammer to the HD and pull your RAM cards. Some hackers can pull code off of your RAM cards even with it powered down. Dont forget that cache on your router guys, I can find tons of info without even exploiting your computer at all, and just pull logs from your router.

I like dd, because it seems old and established. I think one can trust that. I see that you recommend overwriting thrice. I still feel that one write is enough for everything but state secrets. Just how easy is it to recover wiped data on a formatted drive?

I looked in /tmp and did not see a file named 0, 1, or 2, so I guess that is not a file but a literal.

I have not taken a hammer to a hard drive in years, because used drives fetch a good price on Ebay and sell fast. Also, taking a hammer to a hard drive really seems like some kind of environmental crime. And it startles onlookers. I've sold over a dozen used drives. Wiped-once, of course. So far, no determined hacker seems to have recovered enough data from any of them to steal my identity, although one never knows...maybe they decided my identity didn't have enough value. I imagine that hackers would prefer to recover from a drive that had merely had its files deleted, or at the very utmost extreme, formatted.

Interesting tip about router logs--was not aware--but that would not bother me. I don't often sell routers, but I wouldn't mind if someone read my router log.

You have quite an interesting profile picture, there. I like it. Thanks for the tip and good luck with your project, cyanogenic XDA.

[bigj231]

To answer your question about how hard is it to recover data from a formatted drive, I usually tell them to look harder for those backup disks they were supposed to make last week/month. I've had better luck recovering data from dropped hard drives than formatted ones.

[igor83]

To answer your question about how hard is it to recover data from a formatted drive, I usually tell them to look harder for those backup disks they were supposed to make last week/month. I've had better luck recovering data from dropped hard drives than formatted ones.

Once the partition table is whacked, it's really touch and go to piece together where the files are. Not impossible of course, but time-consuming, and in the case where one wants to recover many files, prohibitively time-consuming. I've done this before, using a hex editor to crack copy-protected disks with "invisible" files. Not so bad for one file, but for many, well, that can be rather confusing, especially when disk fragmentation is added to the mix.

I haven't dropped a hard drive in ages (*knock on wood). That would be like dropping a baby! Fortunately drives these days auto-park their heads, so if you do drop them, the damage may not be as severe as back in the day.