Quad Boot OS with separate boot partition

[oldfred]

Some installs give a choice on where to install grub2's boot loader. You can then not install, if an option or install to a partition (Ubuntu's only other option). The install to a partition will never be used and is just to keep your main install's grub2 in the MBR.

If your second install overwrites the MBR but gives the option to boot into Ubuntu your can easily reinstall Ubuntu with this:

#reinstall from working (not liveCD) system - first find Ubuntu drive (example is drive sdb but use your drive not partitions):
sudo fdisk -l
#if it's "/dev/sdb" then just run:
sudo grub-install /dev/sdb
#If that returns any errors run:
sudo grub-install --recheck /dev/sdb
sudo update-grub

If it gets to the point you need a liveCD to reboot.

https://help.ubuntu.com/community/Grub2/Installing
Reinstall grub2 - Short version & full chroot version
https://help.ubuntu.com/community/Gr...alling%20GRUB2

Or you can have Boot-Repair, Supergrub or other boot alternatives.
http://www.supergrubdisk.org/
Boot Repair:
https://help.ubuntu.com/community/Boot-Repair

I also install grub2 directly to a flash drive and manually configure a grub.cfg to boot several other drives either MBR, or to a partition.

Install grub2 to USB -general info
http://members.iinet.net/~herman546/....html#GRUB_USB

[Mr_JMM]

Thanks again.

I seem to have fixed it by leaving Ubuntu using the boot partition and reinstalling the other distros as normal (without assigning a separate boot). Then updated grub from Ubuntu. Used Grub Customiser to change the order and rename them.

Thanks for all your help. Whilst I don't think this achieved everything I set out to do I'll mark this as solved as for now at least, it is the best way I can see of successfully using a separate boot partition.

I have since borked the disk causing errors with gparted but I'll start a new thread on that.