Re: How to recover a root partition with damaged boot blocks

["Thomas Mueller" <mueller6725%twc.com@localhost>]

> things to do:

> - reinstall bootxx_ffsvN -- make sure you're installing the right
>   ffsvN.  you can use "dumpfs <device> | head -2", and it should
>   say FFSv1 or FFSv2 here.  that's "installboot" that you may have
>   already done, but perhaps used the wrong one?

> - re-copy /boot.  cp /usr/mdec/boot /

> - re-copy your /netbsd (where ever it came from)

> - uefi wants a MSDOS partition with /efi/boot/bootx64.efi, so if
>   you haven't provided that it won't work.  if you have enough
>   space at the start or end of the disk you probably can do this,  
>   as it only needs to be pretty tiny.  i did this on a system where
>   root started at sector 2048, and i was able to create about 700KB
>   file system, and bootx64.efi is only about 230KB.  it normally is
>   ok with mbr _or_ gpt partitions here.

> - check that the fdisk (gpt?) and disklabel are OK.  ie, run both
>   "fdisk wd0" and "disklabel wd0" and compare to your working
>   system, see if anything stands out.

HTH,


> .mrg.

Now I couldn't boot NetBSD from either amd64 or i386 installation, there is a breakpoint trap 1, so I never get to login.  But I was able to boot into an old FreeBSD 11.1-STABLE from 2017.

I still have a working but old Seamonkey and xpdf, and icewm; also mutt, mpop and msmtp.  Seamonkey fumbles on some websites that a newer Seamonkey might work on.

I have fat32-formatted partition with /efi/boot/bootx64.efi , but I don't get any uefi in the boot menu except for UEFI shell.
 
Where do I copy the boot kernels to, and how do I get uefi to get the correct one?  How do I get uefi to find the desired boot partition?

Motherboard is old (June 2011), does not always recognize the USB stick that I want to boot from.

Tom