I already dual-boot my laptop with a Windows 7 and an Ubuntu 10.10 partition. Since this is both a development and experimenting system, I made a small 15 GB partition for the purpose of trying out new distros and see what I like. Essentially, this is an experiment partition where I can screw around and see what works and what doesn't.
I installed the beta of 11.10 last week, but don't like it too much as it seems to shift quite a bit towards Windows/Mac GUI-centric usage, while earlier Ubuntu distros were a good split between GUI/CLI interfaces.
My issue is it installed a new GRUB overlay. If I reformat the partition, will the OS links in the bootloader be untouched, or do I have to re-install GRUB after the partition format?
I assume this is all on 1 hard drive.
Yes you will need to update GRUB.
Update GRUB
update-grub2
Next time you boot the 11.10 GRUB option should be gone and you'll be left with 10.10 and windows.
Usually, No
But you may have to re-install grub before partition format. That is the way I prefer it. Just install grub on your primary partition using
grub-setup
.I haven't tried it with 10.10/11.10 but most other OS combinations (Fedora, Ubuntu+1, Ubuntu etc) and it works.
If you are going to test out different distributions or like me, different versions of Ubuntu installed in other partitions then I recommend that you install in your main or working Ubuntu (10.10 in your case) Grub Customizer.
Here is the link.
link to Grub customizer
This excellent utility will let you reorder the grub menu as well as place an image as background. It also has an option in the file menu to Install to MBR.
Wherever one of my other Ubuntus overwrites my 11.04 grub with a kernel update or as Oneiric did recently installed Grub (as happened to you) I boot into my working Ubuntu and run Grub customizer and I use the file menu Install to MBR to put my Natty Grub menu back in place.
Regards.