I have GRUB2 installed on /dev/sda, the usual way (stage 1 in the MBR and stage 1.5 in sectors 0-63); I'm using BIOS/MBR. There are four partitions on my disk:
- Win10 100 MB -- Reserved
- Win10 30 GB
- Linux 20 GB
- Data partition (think of it as
/home) -- the rest of the disk
Stage 2 of GRUB2 is, of course, installed on
/boot/grub/. Now, the question is, can I erase
/dev/sda4 and still be able to boot into Win10 from GRUB's command line manually? Using
insmod ntfs etc., up to
According to wiki, it is OK, but some other sources across the internet suggest that you might get stuck after deleting stage 2 (those sources might refer to the GRUB-legacy, though).
Why do I need to do this? I'd like to extend
/dev/sda2. The most reliable way to do it, as far as I know, is to use standard Win 10 disk partitioning tool (I wouldn't really trust Linux with this). It is supposedly risky doing it while booted into the same partition you're trying to extend, but I've done it and it works fine (there's also some 3rd party software that handles it smoother by extending it in between the boots).
So, I'd like to delete
/dev/sda2/, then boot into Live USB, repartition the unallocated space, install Linux, install GRUB and be done.
I'm only concerned, what if something goes wrong (which usually does), will I be able to boot manually?
There's another way: installing GRUB2 Stage 2 onto a USB (USB comes before HDD in my BIOS boot order) and booting from USB. But that's clumsy (and I've never done it before), so I would prefer to avoid it if possible.
(I did back up, of course.)