hot swap: removing hard drives

[jd1008]

On 06/19/2015 02:35 PM, Chris Stankevitz wrote:
> Hello,
>
> My hardware, caddies, BIOS, OS, etc etc etc all support hot swapping
> drives.  My drives are used only by ZFS.  The zpool on these drives is
> not needed for the system to run.  There are no swap partitions or
> anything else on these drives.  These are /dev/daX drives.
>
> How do I safely remove the hard drives that make up this zpool?
>
> 1. zpool export (of course)
>
> 2. camcontrol stop (is this needed?)
>
> 3. camcontrol eject (is this needed?)
>
> 4. [some other commands?]
>
> 5. verify that /dev/daX is not longer listed (is this needed?)
>
> 6. Yank the drive
>
>
> My guess is that only steps (1) and (6) are needed.  Steps (2) through
> (5) can be omitted.
>
> Thank you,
>
> Chris
I had seen a disk farm where each drive external caddy face had
a button.
To hot remove, one had to push that button, wait for the green light
and the lock/latch would unlock and the operator could then pull
the drive out.
Perhaps FBSD and (all BSD variants and all *nux'es) are not yet
equipped with such sensor reader.