Seeing the dreaded "ZFS: i/o error - all block copies unavailable" on 9.0-CURRENT

[Chris]

So it sounds like somehow my system is trying to use the old boot2
method when I don't hit F12. I'm guessing the difference is due to how
the hard drive is getting presented to the boot loader by the BIOS.
How can I get rid of the legacy boot system and use only the ZFS
bootloader?

On Tue, Feb 23, 2010 at 1:03 PM, Matt Reimer <mattjreimer at gmail.com> wrote:
> On Tue, Feb 23, 2010 at 8:20 AM, John Baldwin <jhb at freebsd.org> wrote:
>>
>> On Thursday 18 February 2010 10:38:38 pm Chris wrote:
>> > > I'm seeing some difference in the bootloader output between using the
>> > > F12 workaround or not:
>> > >
>> > > F12 workaround mode:
>> > >
>> > > FreeBSD/i386 boot
>> > > Default: zroot:/boot/zfsloader
>> > > boot: status
>> > > config:
>> > >
>> > >             NAME     STATE
>> > >             zroot    ONLINE
>> > >        gpt/disk0   ONLINE
>> > >
>> > >
>> > > No F12 key pressed:
>> > >
>> > > FreeBSD/i386 boot
>> > > Default: zroot:/boot/kernel/kernel
>> > > config:
>> > >
>> > >              NAME     STATE
>> > >               zroot    ONLINE
>> > >          gpt/disk0   ONLINE
>> > >
>> > >
>> > > What's up with the differences between the Default boot setting?
>> > >
>> >
>> > Sorry for the spam but I'm seeing something else very interesting....
>> > If I boot to Good Mode (F12) and break to the "boot:" prompt, the
>> > system boots if I type /boot/zfsloader. However, if I type
>> > /boot/kernel/kernel (as was seen in the Default setting when I didn't
>> > hit F12),  I get a crash that looks like the following:
>> > -----------------------------------------
>> > FreeBSD/i386 boot
>> > Default: zroot:/boot/zfsloader
>> > boot: /boot/kernel/kernel
>> > int=00000006    err=00000000  efl=00010882  eip=00200000
>> > eax=0018b070  ebx=ed7706bd ecx=c72e2ca8 edx=00000000
>> > esi=00000040   edi=000929d0  ebp=0009279c esp=00009401
>> > cs=0008  ds=0010   es=0010  fs=0010  gs=0010  ss=0010
>> > cs:eip=ff ff ff ff ff ff ff ff 7f-00 00 00 00 00 00 00 00
>> >            00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00
>> > ss:esp=36 80 0d 07 90 00 00 01-e9 c4 fc ff ff aa ac 84
>> >              c0 0f 84 86 00 00 00 a8-80 74 f2 88 c5 b0 3d aa
>> > BTX halted
>> > -----------------------------------------
>>
>> I'm not sure how well we support booting a kernel from boot2 anymore, much
>> less from zfsboot.  Using /boot/loader (or /boot/zfsloader) is probably
>> the
>> only tested (and realistically supported) case.
>
> Yeah, the last time I tried this it didn't work, but I didn't hunt down why.
> Matt
>>
>>
>