2

I have been using Linux installed on an external hard drive (lets say A) for a year, so everytime my hard drive was connected i could use linux and when it wasnt i could use windows.

Now i have taken another external hard drive(lets say B) and i did the same proccess to install linux.

What i wanted to do was to be able to use both of the external hard drives( A and B) and the internal hard drive that had Windows Unfortunately, when i installed linux on drive B i used as mount point the "/" that was the same i used for drive A

As a result i can now use drive B and internal hard drive but not drive A because the system doesnt find it when booting. When i am using drive B, when i plug in drive A i am able to see the files but not use it as an OS

My question is, can i change the mounting point of drive A since i can not enter it as an OS without loosing the files that are in it, so than when booting i can choose if i want to use drive A,B or internal hard drive?

EDIT: Is Windows in the internal drive running in UEFI mode? Yes Did you install Ubuntu in the external drives in UEFI mode? Yes Did you create separate EFI System Partitions (ESP) in each of the two external drives A and B? I am not sure, I followed exactly this tutorial : https://www.youtube.com/watch?v=YIhYitXwJfE

EDIT2: The pictures from Gparted are here https://i.stack.imgur.com/8kYwp.jpg The first one(with 930.4 Gib) is the external drive B:

enter image description here

and the second is external drive A(the one that i cant enter):

enter image description here

As I said, i cant boot from external drive A, only from B or internal drive.

The page i see when i plug in external drive B is almost like the third picture i found online:

enter image description here

The only difference is that it has the option "Windows boot manager" below the option ubuntu.

What if i change the mount point of drive A to "/"? Will I have problem with drive B?

user68186
  • 33,360
Alexandra Kapa
  • 23
  • Are you making your choice of system from the Grub menu? – Paul Benson Mar 18 '21 at 18:52
  • You can mount drives wherever you like (pros & cons exist for some locations), however when you add an additional mount, it'll shadow (like hide) whatever was visible at that location before hand (it won't be seen, changed or harmed). You have full control on where you mount via the file system table (/etc/fstab) which is read during boot, or on certain commands. Yes you can make changes, I'd suggest via live media (and use external, internal, network etc). Your question's answer as written is a YES. – guiverc Mar 18 '21 at 21:46
  • @guiverc I have understood that the new mount has shadowed the old but I don't know how to make them both visible.Do you know how? – Alexandra Kapa Mar 19 '21 at 13:39
  • @user68186 I have edited the post,check this out please – Alexandra Kapa Mar 19 '21 at 13:39
  • @PaulBenson When i plug in the external hard drive, a screen shows up that lets me choose between ubuntu or windows boot manager, when the hard drive ist plugged in the n I enter windows automatically – Alexandra Kapa Mar 19 '21 at 13:41
  • @user68186 I did what you asked,Check this now if you want. – Alexandra Kapa Mar 19 '21 at 16:35
  • What you intended is not how it works. Have the two drives connected, then reinstall grub so both drives are recognized, or probably better, just use your computer BIOS to select the attached drive to boot from. – vanadium Mar 19 '21 at 17:26
  • Let me know if it works. – user68186 Mar 19 '21 at 21:42
  • To make multiple mount points visible, mount them in different locations. A drive can also be mounted multiple times (pros & cons with this like everything).. my point was you can have whatever setup you like; what works for you, but take note to document it (years to come complex setups can be a pain to maintain...) – guiverc Mar 19 '21 at 21:43

1 Answers1

0

The Issue is not mount-point

If I understand your problem correctly, the issue is not changing the mount point of Drive A to /. When you installed Ubuntu in Drive A, the correct mount point was assigned. However, when you installed Ubuntu in Drive B, some information in the internal EFI System Partition (ESP) was overwritten and updated for Drive B.

This is why you can boot from drive B and drive A does not boot any more.

The Solution is to have ESP in all the drives, A, B, and the internal drive (it is already there).

You have to install ubuntu in Drive A and Drive B again. See Installing Ubuntu in a external hard drive and NOT placing GRUB of my C: hard drive for how to go about doing that.

Repeat the process for A and B.

Finally you have to remove the part of Grub installed in the internal ESP partition. See this answer for how to do that:

Can only boot Windows 10 through grub. How do I disable this?

Once all these are done, it will work a bit differently when it comes to booting from Drive A, Drive B or Internal drive (Windows). Windows will boot by default. When you want to boot from drive A or B, you will have to press the key to select the boot device. This can be F10, F12, Esc, or some other key. This is the same key you press to boot from the Live Ubuntu installation USB. Once you press the key you will see option to boot from the USB drive in UEFI mode. Select that and the computer will boot from Drive A or B.

Hope this helps

user68186
  • 33,360
  • so there isnt a way to do something without loosing my files from drive A? Also, changing mounting point to "/" won't solve it? I thought that as the mounting point for drive A is now /media/alex it can't boot the drive A so thats why it loads it only as files and not as an OS. Is this entirely wrong? – Alexandra Kapa Mar 19 '21 at 17:42
  • You can navigate to /media/Alex/driveA and copy all your files to Windows or to another USB. Drive A can't boot because the part of grub installed in the ESP in the internal drive now points to drive B. Changing the mount point won't fix that. – user68186 Mar 19 '21 at 18:09
  • 1
    ok thank you so much!! – Alexandra Kapa Mar 19 '21 at 18:29