probing LUN's

[Nate Lawson]

On Thu, 24 Jul 2003, Tony Maher wrote:
> > Actually, I don't know that that will cause the device on LUN 4 to show up
> > if LUN 0 isn't probing.  According to SAM-3, all SCSI devices must accept
> > LUN 0 as a valid address.
> >
> > Of course if it does respond on LUN 0, but just says that the LUN isn't
> > connected, we may still end up failing to probe additional LUNs..  It has
> > been a while since I looked at the probe code.
>
> Attempts to use CAM_QUIRK_HILUNS were not successful.
> Following Matt Jacobs pointer to the code I modified cam_xpt.c
>
> I am not sure what you mean by "LUN 4 to show up > if LUN 0 isn't probing".
> There is no device at LUN 0 so the probe will return no device. The existing
> code gives up further probing at this point (no device at lun 0).
> This would appear to be a bug.

It's not a bug, it's behavior defined by the standard.

> configurations) it would be nice if FreeBSD probed all LUNs.
> It isn't a big cost is it?
> If it is could we have a kernel option CAM_PROBE_ALL_LUNS?

Perhaps.  I'll let others address the question of breaking standards
compatibility.  I'm not sure why it's a problem to keep doing "camcontrol
rescan 1:0:4" in your rc.local or something.

-Nate