How does one change grub2's install path on Ubuntu?
by LMtheCat from LinuxQuestions.org on (#5GB2Y)
I installed Ubuntu because I wanted to see how it handles upgrading into the next LTS version. I chose Ubuntu 16.04 because it's near EOL and also because I was curious how smoothly/roughly the upgrade procedure will handle the change in default DE. The installation went well for the most part, except for some reason the installer insists on putting Ubuntu's grub2 on a different HDD. I'm doing the installation on a spare HDD (sdb), and while the rest of the OS went into the correct partition of that disk correctly, the installer always puts grub2 on sda1 (my primary drive's ESP) instead of sdb1 (the spare drive's ESP). During the installation process, I tried specifically clicking the option that says "do not use this partition" on sda1 and marking sdb1 with the "use as ESP" or some such equivalent, but I noticed the Ubuntu folder still ends up on sda1 and there's no sign of it on sdb1.
Now, I know the most straightforward way I might be able to fix this would be to go about the installation procedure again, but this time with sda disconnected from my computer. However, I was wondering if maybe that wouldn't be necessary and if maybe grub2 can be configured from within Ubuntu, which boots properly just fine. I remember back when I tried Gentoo that the bootloader was one of the last steps in its installation procedure. I was about to use it as a reference, but I remembered that in Gentoo, I had to mount the target ESP manually on the specified directory before punching in the command that installs grub2 on the ESP that I manually mounted. I'm not sure if I'd be able to do that in Ubuntu because it automounts the current wrong ESP on that directory. So yeah, is there any way I can reconfigure Ubuntu's grub2 so that I can have it on sdb1? Would I be able to fix it while booted on Ubuntu, or would I have to chroot into it from a live installation? Any help would be appreciated.
Now, I know the most straightforward way I might be able to fix this would be to go about the installation procedure again, but this time with sda disconnected from my computer. However, I was wondering if maybe that wouldn't be necessary and if maybe grub2 can be configured from within Ubuntu, which boots properly just fine. I remember back when I tried Gentoo that the bootloader was one of the last steps in its installation procedure. I was about to use it as a reference, but I remembered that in Gentoo, I had to mount the target ESP manually on the specified directory before punching in the command that installs grub2 on the ESP that I manually mounted. I'm not sure if I'd be able to do that in Ubuntu because it automounts the current wrong ESP on that directory. So yeah, is there any way I can reconfigure Ubuntu's grub2 so that I can have it on sdb1? Would I be able to fix it while booted on Ubuntu, or would I have to chroot into it from a live installation? Any help would be appreciated.