Re: non-functional /usr/mdec/boot? - NetBSD 9_Stable (20210114)

[ignatios%cs.uni-bonn.de@localhost]

On Mon, Jan 18, 2021 at 12:59:40PM -0500, Greg Troxel wrote:
> 
> yancm%sdf.org@localhost writes:
> 
> >> boot hd0:boot
> > boot: hd0a:boot Input/output error
> 
> Have you read your entire disk with dd, and checked SMART?
> 
> > By putting my backup /boot from my previous 8_Stable, the machine
> > boots fine again, no cd required.
> >
> > Could I have goofed up the installboot step? filesystem IS ffsv1
> > and I used the ffsv1 1st stage.
> >
> > For my understanding, does the first stage loader
> > /usr/mdec/bootxx_ffsv1 in my case have to be the same revision as /boot?
> > (ie. both NetBSD 9) Could having them out-of-sync cause this?
> 
> This is often complicated and hard to tell.   I would be surprised if
> this were an issue.

I think this mechanism is pretty robust. I do lots of guerilla
updates (that is boot new kernel, verify that it runs, then tar
--unlink -xpzvf all but etc.tgz/xetc.tgz, then postinstall) and
neglect to update the bootblocks until I want a new feature.

However, what is an issue with your symptoms is output (and input) 
device setting. If I'm not mistaken:

- primary bootblock uses BIOS i/o
- /boot starts with whatever is (nowadays) configures in (via installboot -e)
  and can be further configured via /boot.cfg (if this feature is enabled).

	-is

-