Comment obtenir la fonction "effacement sécurisé" de l'Utilitaire de disque sur El Capitan & Sierra

Allan et Klanomath fournissent tous deux des conseils précis sur la manière de procéder via le terminal. Toutefois, si vous souhaitez effectuer cette opération avec un disque dur (et non un disque SSD), l'option est toujours disponible dans l'Utilitaire de disque, bien qu'elle ait été modifiée.

Suivez les étapes suivantes :

1. Sélectionnez le volume (et non le disque physique). pas un SSD) dans la barre latérale
2. Cliquez sur le bouton Effacer
3. Cliquez sur Options de sécurité
4. Sélectionnez le niveau d'effacement sécurisé dans la fenêtre suivante en déplaçant le curseur. Vous constaterez qu'il existe une option permettant d'écrire de façon aléatoire des données suivies d'une seule passe de zéros sur l'ensemble du disque.

J'espère que cela vous aidera.

L'effacement non sécurisé/sécurisé n'est accessible que par le biais de Terminal >. diskutil zeroDisk|randomDisk|secureErase device .

man diskutil aide :

zeroDisk [force] device
            Erase a device, writing zeros to the media.  The device can be a whole-disk or a partition.  In either
            case, in order to be useful again, zero'd whole-disks will need to be (re)partitioned, or zero'd parti-
            tions will need to be (re)formatted with a file system, e.g. by using the partitionDisk, eraseDisk, or
            eraseVolume verbs.  If you desire a more sophisticated erase algorithm or if you need to erase only
            free space not in use for files, use the secureErase verb.  The force parameter causes best-effort,
            non-error-terminating, forced unmounts and shared-mode writes to be attempted; however, this is still
            no guarantee against drivers which claim the disk exclusively. In such cases, you may have to first
            unmount all overlying logical volumes (e.g. CoreStorage or AppleRAID), or, if a disk is partially dam-
            aged in just the wrong way, even un-install a kext or erase the disk elsewhere.  Ownership of the
            affected disk is required.

 randomDisk [times] device
            Erase a whole disk, writing random data to the media.  Times is the optional (defaults to 1) number of
            times to write random information.  The device can be a whole-disk or a partition.  In either case, in
            order to be useful again, randomized whole-disks will need to be (re)partitioned, or randomized parti-
            tions will need to be (re)formatted with a file system, e.g. by using the partitionDisk or eraseDisk
            verbs.  If you desire a more sophisticated erase algorithm or if you need to erase only free space not
            in use for files, use the secureErase verb.  Ownership of the affected disk is required.

 secureErase [freespace] level device
            Erase, using a secure method, either a whole-disk (including any and all partitions), or, only the free
            space (not in use for files) on a currently-mounted volume.  Erasing a whole-disk will leave it useless
            until it is partitioned again.  Erasing freespace on a volume will leave it exactly as it was from an
            end-user perspective, with the exception that it will not be possible to recover deleted files or data
            using utility software.  If you need to erase all contents of a partition but not its hosting whole-
            disk, use the zeroDisk or randomDisk verbs.  Ownership of the affected disk is required.

            Level should be one of the following:

                  o   0 - Single-pass zero-fill erase.

                  o   1 - Single-pass random-fill erase.

                  o   2 - US DoD 7-pass secure erase.

                  o   3 - Gutmann algorithm 35-pass secure erase.

                  o   4 - US DoE algorithm 3-pass secure erase.