I have 2 hard disks — a 240 GB SSD and a 2 TB standard disk. I put Windows, Linux Mint, and Ubuntu 16.04 on the SSD, the sda and Fedora and Kali Linux on the 2 TB disk, sdb.
Now, as I was installing the systems (I installed them in the order Windows, Linux Mint, Ubuntu, Fedora and Kali Linux) until I exhausted the space in sda while installing Ubuntu, the grub menu kept changing as per the latest OS installed. Meaning, when I was done installing Linux Mint, Mint's grub2 menu had showed up during PC boot, and likewise, after I followed it up with Ubuntu's installation, Ubuntu's grub2 showed up. Now, I proceeded to install Fedora, followed by Kali Linux. But this time around, I see that same Ubuntu grub2 menu is being displayed. Also, in order to select Fedora or Kali, I need to press my boot options key F11 (MSI motherboard), where it shows Fedora and Kali. If I select and proceed with either, I'm able to boot to the respective system.
Tinkering around in Ubuntu, I tried the following:
sudo os-prober
sudo update-grub
These commands did the job and added Fedora and Kali to the Ubuntu's grub2 menu.
Now, I would like to know:
- Why has Ubuntu's grub2 assumed the role of native bootloader?
- How to make any grub2 menu as the native bootloader in cases similar to mine, i.e, when multiple Linux distros and/or multiple hard disks are involved?