WIPE DATA OR HARD DRIVES SAFELY & IRRETRIEVABLY

 

WIPE DATA OR HARD DRIVES SAFELY &  IRRETRIEVABLY

 

When we are going to erase the data from our hard drive (for example, we send it to the Windows trash, and then empty it), the file will have disappeared from its original folder. However, the file has not actually been deleted, it is still on the hard drive; its space has simply been marked as "free" and is waiting for another file to overwrite its data and take its place. The same happens when we format the hard drive. Its surface is marked as "free", but in reality the data is still there.

While this file is still here, it is possible to recover it using data recovery programs, very simple software to use that, probably, on more than one occasion, has saved us from some displeasure. Even if the data has been overwritten by other files, using forensic techniques it is possible to reverse these changes and revert to the original data.

Beware of SSDs

Everything that we are going to see next is designed to eliminate data on conventional hard drives, HDD. If we have an SSD, of course these commands and programs will also work and fulfill their function. However, these work very aggressively, doing a lot of writing to the drives. And this can damage our SSDs or reduce their lifespan considerably.

Most modern SSDs have a system called TRIM. Thanks to it, the data that is deleted is usually erased permanently, and it is not necessary to resort to overwriting techniques to ensure its disappearance.

Safely erase a hard drive from Linux

Most Linux distributions come by default with a series of tools that will allow us to safely delete any type of information that we may have on hard drives. What these tools mostly do is erase the data and overwrite the information with other random information. And so on several times.

We can use any Linux distro to use the following tools, although the best thing is that we use a distro that loads directly into RAM. An Ubuntu Live, and even a recovery distro like SystemRescueCd will allow us to perform this task without problems.

DD

The DD command is one of the most comprehensive Linux data copy commands. We can use this command to replace all the data on a hard drive with random information so that the data is overwritten and cannot be recovered. To do this, what we must do is execute the following command, selecting the drive (hard disk or partition) that we want to clean instead of / dev / sda.

We can execute this same command 4 times so that the data has been overwritten 4 times with totally random information, and thus it will have disappeared completely.

DATA Shred

This is a tool, included in Linux distros, specially designed to safely delete data by overwriting its space with random information. To do this, what we must do is run the program, followed by the number of times we want to overwrite the data, and the drive we want to clean, to safely destroy all the data on that drive.

The -vz parameters allow us to see the overwriting process in the console, and, when finished, make a last pass to overwrite all the data with "0", leaving the drive completely clean. We can also add the "–random-source = / dev / urandom" parameter to use the urandom function of Linux distros instead of their own algorithms.

DATA WIPE

Another tool similar to the previous one that, as its name suggests, allows us to clean our hard drive, destroy its information and prevent the data from being recovered again.

SCRUB

And finally, let's talk about scrub. This tool has also been developed to allow us to overwrite all the information on any hard drive or storage device. This tool repeats patterns so that reverse engineering techniques have it much more complicated when trying to recover the information. This program uses several different algorithms so that the data is practically impossible to recover.

Using programs to irretrievably erase data

We may not want to use the Linux console for whatever reason (usually scary). For this reason, we are also going to talk about other programs that help us to safely delete specific files from the hard drive, in addition to deleting any hard drive safely.

DBAN

DBAN is a free program designed to completely erase any hard drive and also overwrite all the information on it with random data. This program runs in Live mode, as an independent operating system from RAM, and allows us to choose the drive we want to clean and a series of parameters (such as algorithms or number of passes) so that the cleaning is as accurate and complete as possible .

HDD Low Level Format

Another program to erase data safely is HDD Low Level Format. What this program does is completely empty any disk or unit that we select and, later, it allows us to initialize it, marking all sectors of the hard disk to "0".

Eraser

Eraser is a program for Windows whose purpose, as the name indicates, is to allow us to erase the files we want. Instead of erasing hard drives or entire partitions, this software integrates into the Windows context menu so that we can erase any individual file, safely and irretrievably, simply by right-clicking on it.

Permadelete

Yet another alternative, for those who prefer open source software, is Permadelete. This program has a very easy-to-use interface to be able to delete any Windows file or folder so that not even the slightest trace of the file remains at the end, and it is also impossible to recover the smallest information about it.

Fire and destruction

Surely there are times when we have stored information on our hard drive that is too important for it to fall into the wrong hands. The above methods can help us delete this data and make it impossible to recover. But there is always the doubt and the minimum possibility that, in the end, this information can be recovered.

If all of the above does not give us enough confidence and we do not want to risk it. The best we can do is completely destroy the hard drive. And here we can give free rein to our imagination.

The most common, in the case of normal hard drives and SSDs, is to start destroying them with a drill. We must make several holes throughout the surface of the unit, especially in the plate of traditional hard drives, so that it is as destroyed as possible. Next with a hammer, we must make sure that the plates (in the case of a conventional hard drive) or the memory chips in the case of an SSD are as ground and destroyed as possible to avoid any recovery attempt.

The fire can also help us to destroy any remaining debris, further reducing the likelihood that recovers nothing. And finally, we must throw the remains in different containers, avoiding even more that they get the parts that give them this recovery.

This is the most paranoid method of erasing data. But it never hurts to take note.