I currently have Xubuntu installed on my laptop. It's the only OS, the laptop only has one SSD drive and that drive is encrypted.

I'd like to add a second SSD drive to the laptop and install Linux Mint on that new drive.

I believe the process would simply be to boot from a live USB of Linux Mint and install it to the second hard drive.

Once that install is complete, reboot the laptop into Xubuntu on the first drive and do:

sudo update-grub

Then reboot into Linux Mint on second drive via UEFI boot selection and do:

sudo grub-install /dev/sda

Doing this would update Grub with both distinct Linux distros and present a menu at laptop startup to choose from.

Is that the correct steps for installing the second distro? Does the fact that the first SSD being encrypted have any considerations in dual-booting this way?

Thank you.

  • No, the second step (in Mint) will override what has been correctly done in first (and is incorrect for UEFI). – user692175 Sep 30 '17 at 18:29
  • A similar question was replied recently in a rather detailed way at this link, askubuntu.com/questions/960660/… . I think you can get some tips from there. -- Are you booting in BIOS mode or UEFI mode? – sudodus Sep 30 '17 at 18:45
  • 1
    When booting in UEFI mode it is best to keep booting via the existing EFI System Partition, ESP, and not try to have a second ESP on the second drive, if both drives are internal. The situation is different if you install the second system into an external drive, and expect it to be portable between computers. In both cases you should do the sudo update-grub task (in the system, that will be considered the primary one). – sudodus Oct 1 '17 at 19:44
  • 1
    No, I would not run the command line sudo grub-install /dev/sda. – sudodus Oct 2 '17 at 4:38
  • 1
    In BIOS mode, yes, but in UEFI mode the boot is via the ESP. I think you cannot stop that unless you disconnect the internal drive. The ESP is where Linux Mint should write its things in order to be booted into (I don't know how good Mint is at these tasks). If you want to disconnect the internal drive, fine; install Mint, connect the internal drive and then run sudo update-grub in Xubuntu, and it should find Mint and add a menu entry for it. -- If things go wrong, you can try to repair the boot system with BootRepair according to this link, help.ubuntu.com/community/Boot-Repair – sudodus Oct 2 '17 at 12:51

The PC boot loader lists the partitions that are marked as bootable. In Linux, these are partitions where /boot folder is. Systems always starts from a designated partition on a designated drive. The grub settings there dominate. Generally, the second OS that is installed will always rewrite grub settings. That second installer must be aware of the other OS's boot partition so as to launch it. For me, it always works best to have that second install take notice of the OS and add it to the list. Do that in installation, not later, if possible. It is much more likely to turn out right.

If you install Windows first, then Linux, then the Linux bootloader inserts itself into the startup process first. Installer will generally ask you if you want to take notice of other OS and launch them. Most people understand that. Vice versa, install Windows second, it ignores Linux, replaces the OS boot loader, and you have only Windows. Your case is different b/c your 2 OS are more tolerant, the second one will usually be more aware/generous of other OS.

Which drive? Which partition? The BIOS and drive layout are in charge.

When you look at the drive list in fdisk, you see a star by the bootable partition, one per drive in your case. Well, maybe some drives have none. The BIOS drive ordering determines which drive is found first and labels it sda. That first-found drive has a list of bootable OS partitions. That boot list gets rewritten by every install (each time you run grub install, either in the install or later). You must add each desired OS to the settings inside the second OS so this will work.

At install time in second OS, you have choice on where grub is installed; either in master boot record or a partition. Seems like we always use the mbr now, IDKW.

IMHO this was easier 10 years ago because the booter was not supposed to do as much automatically. Configuration of grub was just a single file list of OS stanzas. You'd edit that, then restart. Every boot would list all the OS. It is still that way in RedHat EL. Seems harder now in Ubuntu to get your brain around it.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.