> 
> 
> mlh@goathill.org said:
> > Can drvctl(8) and atactl(8) be used to attach and detach the esata
> > drive
> 
> No, sorry. bus rescan by drvctl needs a "rescan" method to be implemented
> by the driver. I believe I'm the only person who implemented such methods
> so far, and I didn't dare to touch the ata probing stuff because this is
> known to be hairy (and the way ATAPI is handled doesn't make it easier).
> I don't have any experience with ESATA -- is there any real hotplug
> detection? Does it use AHCI and or SAS?

It is hotplug, but I don't think it has hotplug detection. As far
as I can tell, it's just SATA with better cables and connectors
(hotplug, more cable shielding, more insertion cycles, longer,
metal-shielded connectors).

http://www.sata-io.org/esata.asp

What I got was an external enclosure that accepts 3.5" SATA drives
that can do esata and usb2 that I paid $22 for. It comes with a
rear slot adaptor with std sata cables that just plug into your
host sata controller and allow the esata cables to be plugged in
from the outside.  Pretty nice box actually:

http://websign.net/catalog/product_info.php?products_id=131

Hot swap detection would be nice, but for the speeds it can do,
I'd be more than happy to manually rescan in order to mount it as
a backup device that I share across several computers. Right now,
I'm using it with usb2 so I don't have to reboot to see it.