Dual drive dual boot questions

[SirJohn]

Hello,

I am considering installing Linux on a UEFI laptop with 2 M.2 SSD drives and Windows already installed on one; I would like to keep it for the time being, and install Linux alongside it, that is, as a dual boot, on the second drive (namely, dual drive dual boot, since I understand Windows updates can cause problems with the bootloader if one is shared by both OSs).

However, since I am still testing, I would prefer to install Linux on only a partition on the second drive, rather than all of it, possibly expanding it later if everything goes well.

Thus, the question - would this be possible to do, and how? Would there be any reason not to? Anything additional/different from the case when the second OS is installed on the whole drive?

Related to this, how to go about partitioning the device (in this case, partition) where Linux is installed - I have come across some suggestions of up to 4 (sub)partitions - one for boot, one for root, one for swap, and one for home - however, if future resizing is likely, I suppose this could become somewhat of an issue.

Also, since I have seen recommendations to remove physically the drive with the first OS while installing the second, and this can be a problem on a laptop, can the first drive be disabled from BIOS instead?

I think I will stop here for now.

Should any further information be necessary, please do let me know.

Thanks.

 

[CaffeineAddict]

welcome to the forums!

would this be possible to do, and how?

It depends on distro installer, I don't know which distro you'll be installing but Debian has expert option which lets you manually partition drive prior installing.

Would there be any reason not to?

Partitions can be resized only to the end of partition table, so if your secondary partition is right next to Linux partition you'll need to delete it if in the future you want to resize Linux partition.

To avoid this you'll need to create 3 partitions in total at least, 1st for Linux, 2nd for expansion of Linux (this can be free space in the middle), and 3rd put at the end which you intend to use for what ever you plan to.

Anything additional/different from the case when the second OS is installed on the whole drive?

swap partition is usually put to the end of drive so you'll need to calculate how much size to reserve for expansion of Linux partition, it makes things more complicated, if you go for 3 partitions above then swap partition should be between 2nd and 3rd partition, so in total 4 partitions.

Related to this, how to go about partitioning the device (in this case, partition) where Linux is installed - I have come across some suggestions of up to 4 (sub)partitions - one for boot, one for root, one for swap, and one for home - however, if future resizing is likely, I suppose this could become somewhat of an issue.

This is not needed, just go for 1 root, 1 EFI, 1 boot and 1 swap partition.
boot partition should be 1GB size, swap partition should be at least the size of your RAM, EFI partition needs to be between 512MB (minimum) to 1GB (recommended), and it should be the 1st partition, and root partition should take the rest.

Partition layout is:
EFI, Boot, root, swap
OR
EFI, Boot, root, [reserved size for expansion] swap [custom partition]

This partition layout if for GPT partition table and UEFI boot. (not CSM/MBR)

 

[wizardfromoz]

I have to leave for my evening, now, but I have alternatives to a number of points detailed above.

If I were the OP I would leave it until I can outline them.

His choice, of course.

Cheers

Wizard

 

[SirJohn]

No rush, I would like to hear (read?) what people have to say...

 

[dos2unix]

Some distro's (in fact most) require more than one partition. Usually at least an efi partition in addition to the OS partition.

 

[wizardfromoz]

@SirJohn , do you have a particular Linux Mint distribution eg Linux Mint, Ubuntu, Fedora or other, that you are thinking of installing, at this stage?

I am considering installing Linux on a UEFI laptop with 2 M.2 SSD drives and Windows already installed on one

Is there any data on the 2nd SSD, and did the rig ship with both drives in it?

Quite often, computer resellers will ship or sell a 2-drive rig with MS Windows recovery software stored on the 2nd drive.

Wizard

 

[SirJohn]

Thanks to everyone who posted.

Some distro's (in fact most) require more than one partition. Usually at least an efi partition in addition to the OS partition.

Yes, that, of sorts, is the idea of 2D2B (dual drive dual booting), as I get it.

@SirJohn , do you have a particular Linux Mint distribution eg Linux Mint, Ubuntu, Fedora or other, that you are thinking of installing, at this stage?

After trying 10-ish or so distributions in live sessions, I think I'd opt for CachyOS (Arch-based, I know...).

Is there any data on the 2nd SSD, and did the rig ship with both drives in it?

Quite often, computer resellers will ship or sell a 2-drive rig with MS Windows recovery software stored on the 2nd drive.

There is a bit of something at the moment, but nothing too huge; the machine came with one drive only, I added the second, as well as Windows, it wasn't preinstalled.

 

[dos2unix]

Yes, that, of sorts, is the idea of 2D2B (dual drive dual booting), as I get it.

I'm not real sure what you mean here. But on my dual boot systems ( some are quad boot ). Each disk has it's own efi partition.
No disk knows anything about any of the other disks. I pick where I want to boot from in the UEFI.

 

[The Duck]

I've always used a separate hard drive for each OS.

Each OS used there oem boot loader.

At the time of each OS install only one hard drive connected.

When finished all hard drives connected,

At startup a boot menu displayed and I was able to choose which hard drive I want to boot from.

Never had any issues or problems between OSs.

Don't know how method works with UEFI / EFI secure boot.

My computers were legacy bios.

 

[MikeWalsh]

Never had any issues with multiple Puppies; currently a baker's dozen (& counting), all "installed" within uniquely-named directories on the same partition. But then Puppies are sociable creatures; they're happiest in a big "puppy pile", and are designed to co-exist peacefully with each other.

They're also probably about the ONLY distros that can be installed actually inside another OS! Puppies were designed to install within Win XP 20+ years ago. They were constructed to install by simply clicking on an .exe file......and every Windows user knew how to do that.

But that's esoteric "mumbo-jumbo" from ancient history. I don't wish to confuse the OP any further...


Mike.

 

[SirJohn]

I'm not real sure what you mean here. But on my dual boot systems ( some are quad boot ). Each disk has it's own efi partition.
No disk knows anything about any of the other disks. I pick where I want to boot from in the UEFI.

I've always used a separate hard drive for each OS.

Each OS used there oem boot loader.

At the time of each OS install only one hard drive connected.

When finished all hard drives connected,

At startup a boot menu displayed and I was able to choose which hard drive I want to boot from.

Never had any issues or problems between OSs.

Don't know how method works with UEFI / EFI secure boot.

My computers were legacy bios.

Well yes, exactly - that is the idea of multi-drive booting, that each one is "independent" of the others, is it not so? In this way, if there is any problem with one OS starting, the computer is still bootable using the other?

This is not needed, just go for 1 root, 1 EFI, 1 boot and 1 swap partition.

Maybe I am getting something wrong, but - is the EFI not the "boot" partition, in that that is where the OS is started from?

 

[CaffeineAddict]

Maybe I am getting something wrong, but - is the EFI not the "boot" partition, in that that is where the OS is started from?

No, EFI partition format is vfat or fat32 while Boot partition format is ext4 or ext2
EFI partition is automatically mounted at /boot though so it looks like same thing but in fact are 2 partitions with different file systems.

Also EFI partition is for boot loaders while Boot partition is for boot manager files like GRUB.

 

[SirJohn]

No, EFI partition format is vfat or fat32 while Boot partition format is ext4 or ext2
EFI partition is automatically mounted at /boot though so it looks like same thing but in fact are 2 partitions with different file systems.

Also EFI partition is for boot loaders while Boot partition is for boot manager files like GRUB.

And so, it would be necessary to have one on the drive to boot from it - thus, one on each drive?

 

[CaffeineAddict]

And so, it would be necessary to have one on the drive to boot from it - thus, one on each drive?

Boot partition is only needed on Linux drive, Windows does not need it.
However EFI partition, you want to have a separate one on Linux drive independent of the one on Windows partition so that Windows can't mess up with it.

Technically only 1 needed, on drive which is set to boot first in BIOS.

 

[MikeWalsh]

@SirJohn :-

And so, it would be necessary to have one on the drive to boot from it - thus, one on each drive?

There's all sorts of "technical" points pertaining to this stuff, but.....yes; if you install a boot-loader to each drive (for the OS on that drive), then each drive can be fired-up independently of the others. And the simplest way to select them would be via the "one-time" boot Menu.

Most rigs have one somewhere.

The other alternative is to choose one drive to always boot, allow that one to boot from its installed bootloader, then add additional entries to GRUB2 that will "chainload" the bootloader(s) on the other drive(s).

Multi-boot grub ( "Chainloading" )

The above blog describes it as simply as possible. And it's easy to do.


Mike.

 

[SirJohn]

There's all sorts of "technical" points pertaining to this stuff, but.....yes; if you install a boot-loader to each drive (for the OS on that drive), then each drive can be fired-up independently of the others. And the simplest way to select them would be via the "one-time" boot Menu.

That seems to be -exactly- the idea; now on to how to do it.

If Cachy uses Calamares, would it be able to set things up automatically, or would manual work have to be done?

And, of course, back to the original question of does installing on only a partition, rather than the whole drive, change anything essential and if so, what to do (differently)?

 

[SirJohn]

Nothing more to say, then?