How can I restore grub for fresh dual boot with Windows with two different disks?

I have two different disks: /dev/sda and /dev/sdb. sda is an SSD disk while sdb is HDD.

Today I installed fresh Windows to sdb for some reason. Naturally, Windows stole the boot priority and disabled grub.

I wanted to restore grub, applied the article below:

https://wiki.manjaro.org/index.php/GRUB/Restore_the_GRUB_Bootloader

However, after what I’ve done, still Windows start by default.

How can I restore grub if:

  • I have dual partition with Windows,
  • Windows is second-installed system
  • and two systems are on different disks?

Thanks in advance.


Environment

Manjaro 21.1.3

As you did not mention if Manjaro and its bootloader is installed on sda or sdb, this is hard to say. If Manjaro was installed on sda, just make sure your firmware boots into sda where Manjaro’s grub is installed.

Why did I never think about this? I’ve just changed the boot order and took the sda to the first place and it works.

A note to the readers

While this is the solution to fire up GRUB on boot, Windows is not shown as an entry since the two systems are on different physical devices. I don’t know how to solve this, probably it can be solved with configuring GRUB manually or GRUB Customizer. However, as Manjaro is my primary environment, I don’t have any problem directly booting it up.

To switch to Windows on bootup, each time you have to trigger boot selector (usually by tapping F8, F2 or DEL continuously) and select the other device.

1 Like

You need to enable OS Prober in GRUB config file (GRUB_DISABLE_OS_PROBER=false), then update grub (sudo update-grub) for the menu entries to get updated. If it doesn’t detect Windows then your OS are not installed the same way (one MBR the other EFI), for OS Prober to detect the second OS, both OS need to be installed the same way.

This topic was automatically closed 2 days after the last reply. New replies are no longer allowed.