Hot Swapping SATA drive?

Polytropon freebsd at
Tue May 14 12:55:24 UTC 2013

On Tue, 14 May 2013 07:45:21 -0400, Robert Huff wrote:
> Ronald F. Guilmette writes:
> >  1) Given a system running FreeBSD 9.1-RELEASE, is anything bad
> >  gonna happen if I insert a drive into this thing while the system
> >  is running?  Will I be able to mount partitions contained on the
> >  drive in question after I do so?
> 	That works for me.  I need to re-scan the ata channel using
> "atacontrol" but once that happens it's fine.

Isn't that supposed to be "camcontrol" today?

I've been using SCSI "hot swap" devices for many years, and
they usually required a re-scan of the bus. The same often
works for USB-connected devices which also use CAM, and maybe
SATA and eSATA also support it today?

> >  2) Given a system running FreeBSD 9.1-RELEASE, is anything bad
> >  gonna happen if I remove a drive from this thing while the system
> >  is running, assuming that I have already properly umounted all
> >  relevant partitions first?
> 	Nothing bad happened to me.

Again, it may be nice (to the system) to detach the ATA device
from the bus; see "man atacontrol" (and "man camcontrol" in
comparison) for the proper command to do this. From the "electrical
point of view", there should be no problem.

> >  3) Assuming that I want to do this stuff, what BIOS options
> >  should I be setting or unsetting on the motherboard?
> 	I am unable to check the BIOS settings on that MB (which may be
> ASrock as well), but I don't believe I had to do anything other hand
> make sure eSATA was enabled.

The only thing that might be worth looking at in the CMOS setup
would be the "method" of the driver, making the device come up
as da0 (for example) or ada0, depending if EHCI or XHCI can be
selected. But I assume this only applies to USB devices (and
maybe Firewire). SATA should work fine with the default settings.

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

More information about the freebsd-questions mailing list