Re: SSD erase question
- In reply to: J. Hellenthal: "Re: SSD erase question"
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Date: Mon, 21 Mar 2022 13:05:35 UTC
Think I've mistaken dc3dd for bcwipe from ports. See bcwipe instead... https://www.jetico.com/news/jetico-delivers-new-bcwipe-solution-wipe-drives-supporting-mac-nvme-secure-boot -- J. Hellenthal The fact that there's a highway to Hell but only a stairway to Heaven says a lot about anticipated traffic volume. > On Mar 21, 2022, at 07:52, J. Hellenthal <jhellenthal@dataix.net> wrote: > > Personally I would use dc3dd from ports and you'll be plenty alright. > > While dd would be enough in most occasions I won't assume your data is of a typical user. It only writes the random bits to the disk once. In some scenarios it's possible to reverse that. dc3dd takes care of that by writing multiple times. > > There is also dcfldd which was superseded by dc3dd. > > -- > J. Hellenthal > > The fact that there's a highway to Hell but only a stairway to Heaven says a lot about anticipated traffic volume. > >> On Mar 21, 2022, at 07:15, Damian Weber <dweber@htwsaar.de> wrote: >> >> >> Hi all, >> >> I'd like to have an answer on a secure FreeBSD way to erase >> SSDs before giving these away to someone for reusing it. >> >> Is the following enough to protect confidential data >> previously stored there? >> >> 1) dd : overwriting with random bits (complete capacity) >> 2) gpart create >> 3) gpart add >> 4) newfs >> >> Details for an example with /dev/ada1 see below. >> >> Thanks a lot, >> >> Damian >> >> >> # fdisk ada1 >> ******* Working on device /dev/ada1 ******* >> parameters extracted from in-core disklabel are: >> cylinders=484521 heads=16 sectors/track=63 (1008 blks/cyl) >> >> Figures below won't work with BIOS for partitions not in cyl 1 >> parameters to be used for BIOS calculations are: >> cylinders=484521 heads=16 sectors/track=63 (1008 blks/cyl) >> >> Media sector size is 512 >> Warning: BIOS sector numbering starts with sector 1 >> Information from DOS bootblock is: >> The data for partition 1 is: >> sysid 238 (0xee),(EFI GPT) >> start 1, size 488397167 (238475 Meg), flag 0 >> beg: cyl 0/ head 0/ sector 2; >> end: cyl 1023/ head 255/ sector 63 >> The data for partition 2 is: >> <UNUSED> >> The data for partition 3 is: >> <UNUSED> >> The data for partition 4 is: >> <UNUSED> >> >> # gpart show ada1 >> => 40 488397088 ada1 GPT (233G) >> 40 1024 1 freebsd-boot (512K) >> 1064 480246784 2 freebsd-ufs [bootme] (229G) >> 480247848 8149280 3 freebsd-swap (3.9G) >> >> # dd if=/dev/random of=/dev/ada1 bs=512 count=488397088 >> >> # gpart create -s gpt ada1 >> >> # gpart add -t freebsd-ufs ada1 >> >> # newfs -U /dev/ada1p1 >> >>