zpool detach pool device

Fritz Wuehler fritz at spamexpire-201201.rodent.frell.theremailer.net
Wed Jan 25 07:17:00 UTC 2012

> All DBAN does is write {whatever-source-you-choose} to the drive
> basically with dd (it's actually a separate wrapper program but it
> behaves identically to dd).

Just use dd and avoid the hassle of downloading and burning a cd that does
dd. dban is nice if you have to do a garage full of machines or are a
Windows victim but if you know your way around UNIX why bother with dban?

I recently had some drives fail and I did dd from /dev/urandom

> 4) If you ever plan on re-using this drive in a system, please do not
> use the PRNG method or similar methods ("write random jibberish all over
> the drive").  This is almost guaranteed to confuse a system (ANY system)
> the next time you insert the disk; data is written to the MBR and
> partition table regions which is gobbledegook, resulting in the
> underlying BIOS, OS, or anything else trying to parse that data, and
> thus begins behaving weirdly/oddly ("what do you mean I can't partition
> this disk?"  "Yeah, there's an HP/UX partition on this thing,
> right...").  I speak from personal experience on this matter.  As such,
> I always advocate people zero their drives and not to pick the defaults.

Interesting. I have never had this happen but I always partition the drives
or label them before trying to do anything after a spring cleaning.

If this is your only objection to nonzero values it still is a good
compromise to dd the whole drive with /dev/urandom and then just blast the
MBR from /dev/zero its only 512 bytes.

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