How to safely remove data from a disk in OS X El Capitan

securely erasing disks function without the possibility of recovery has always been in the "Disk Utility", but in OS X El Capitan Apple removed it. Fortunately, the process of deleting data securely without the use of third-party apps are still there.

If you are concerned about why Apple do so, the answer is quite simple: because of the specifics of the solid state drives them secure erasing inefficient, and in fact all the new Mac is completed SSD. Some people OS X El Capitan installed on a Mac with conventional hard drives, and external hard drives in the HDD also has not been canceled. In general, a secure erase is still relevant.

It is a way for advanced users who understand the essence of the secure erase. Before any manipulation with the disc, particularly the system, do not forget to make a backup copy.

secure erase command, which, in fact, runs through the "Disk Utility", available from the "Terminal". But before you use it, let's see, what are the methods of secure deletion of data.

In OS X are five different ways - from fast to extremely effective:

• One-pass erase, overwriting with zeros. This is the fastest option.
• One-pass erase, overwriting with random numbers. Too fast, but instead of using a random number of zeros.
• Semiprohodnoe erasure standard US DoD. Seven times more reliable and just as long.
• Erase Gutmann method in 35 passes. Multiple overwriting random numbers with alternating sequences. Extremely reliable, but for a long time.
• Erasing in three passes. It requires relatively little time to complete.

Each of these methods is included in the addition command key from 0 to 4, respectively. The team itself is as follows:

diskutil secureErase freespace

Adding to her figure for a method and Paths. For example, to erase the zeros in one pass Transcend flash drive I get this:

diskutil secureErase freespace 0 "/ Volumes / TRANSCEND"

It remains to wait until the operation is completed, and the data from your hard drive, no one will ever be able to recover.

The time that takes erasing depends on the selected method and the disk volume. Be patient, and in any case, do not interrupt the process!

Why even the common man to erase the disc? Here is a simple example. You bought a new Mac, or simply drive for backups Time Machine, and old equipment you want to sell or give away to someone of the familiar. You do not want someone to dig into your personal data? U.S. too.

SSD-drives for safe removal of irrelevant due to the specific information recording units on them, so to protect your important data is better to use FileVault encryption or third-party solution.