Solus lost booting ability due to dual booting with another Linux

elfprince I have installed an Ubuntu type linux os on my second ssd. Immediately after booting, my Solus became unbootable, ie the booting goes straight to Ubuntu.

that's the curse of grub. always will, and always will be.
there's a command to update solus in ubuntu so ubuntu can see the solus bootloader. let me see if I can find it.

Also, as short as I can do it:
two disks, two operating systems, install without unplugging the one: Always Problems
two disks, two operating systems, install on with the other unplugged=Never Problems

in other words I don't know how to do this stuff correctly. if I just unplug then installs works. then plug them both back in. when I boot I spam F11 til the boor menu lets me choose one. I am used to this. Neither interfere with each other.

if you installed Ubuntu in UEFI then there is no grub and this command won't work:

sudo grub2-mkconfig -o /boot/grub2/grub.cfg

that should make Ubu see SOlus bootloader. And I dusted it off from my Fedora tricks list of way back..

others may rccomend refind to fix the boot, but that program has never done anything for me

elfprince yeah, then those /folder structure must be Fedora only. I've seen that command mentioned in other threads, maybes there's a Debian (ubu) version of it?

so linux lite you can install next to solus (two disks) and it's always successful? that's good then.
It's still linux--multiple installs can be like pulling teeth

brent that's the curse of grub. always will, and always will be.

elfprince Grub doesn't see Solus at all.

I can't imagine why anyone would use GRUB these days. I haven't used it for years. Are some motherboards just not compatible with EFI? Does GRUB offer advantages I don't know about? There must be some good reason why people are still fussing with GRUB. Can someone please help me understand?

@"WetGeek"#p86438I don't know if a user would use it intentionally. It's my impression that 75% of distro installers are grub and maybe 25% are efi bootloader like solus? or 65/35? I think Grub is something a user is saddled with.

elfprince see what @murbert says but I don't think copying over will restore it. I think if you want to salvage solus boot you have to do the chroot thing in the help center. I've done this to restore boot too, it's hard but it has worked

elfprince I have always reinstalled when this happened, so I dunno.

This is an old comment that I feel might be helpful again today. This is the functional equivalent to disconnecting the drive you are not installing to when dual booting

You do not say what your partition scheme is. Are all distros on the same disc or on their own? Solus will require it's own => 512MB fat32 boot/efi partition or it's likely to get corrupted eventually.
From a previous post, not entirely relevant but some useful info regarding changing flags. Start at step 5
"You're in a bit of a tricky situation. Are you willing to wipe your computer to do this "right"? If yes, this is what I would do in your situation:
1 - Backup all important data
2 - Make sure you backed up all important data
3 - Running in a Solus live USB, with GParted, wipe drive by deleting all partitions. Then make an ext4 partition of whatever size you want Solus to occupy. Hit the check button to run the commands. This is a placeholder to keep Windows from recognizing the space. Keep the rest unallocated
4 - Install Windows. It will automatically use the unallocated space. Run all updates Windows wants you to run. Reboot and make sure all updates and drivers have been added
5 - Reboot to a Solus live USB, with GParted, change the flag of the Windows EFI partition to msftdata (right click the partition, select manage flags). Delete the ext4 placeholder partition. Create a 1024MB (525MB is good too) fat32 partition. Create a swap partition (I use 4 - 8 GB). Create an ext4 partition with the rest of the unallocated space. Hit check to run the commands. Change flag of the new fat32 partition to boot, esp.
6 - Install Solus to the swap and ext4 drives you just made. It should select the new fat32 drive for EFI automatically. Make sure it does. If so, hit install
7 - Update Solus (sudo eopkg up -y)
8 - In GParted, change windows fat32 partition flag back to boot, esp. (Optional: change flag of Solus EFI partition to msftdata, updates run fine and Windows won't trash it)
9 - Profit

Alternate version, things are a bit fuzzy here, be careful:
Resize the main Windows partition (basic data partition), reducing it by the amount you want to use for Solus. I think you can do this with disk manager in Windows but you may need to use GParted in Solus live. The advantage with Disk manager is Windows automatically recognizes this change. If you use GParted, Windows will have problems and it will want to self repair. Allow any repair requests Windows makes. Create partitions as outlined above in this space you just made

The biggest problem with the alternate version for me is the Solus partitions are in the middle of the Windows partitions. It's messy and ruffles my OCD. Also much harder to keep track of the partitions later.

also as weird as it sounds go in live CD, then gparted, then make sure solus boot is set boot, esp .
shut down.
unplug ubuntu.
then boot solus?

if you did chroot right (I dont always do it right) then an eopkg up (when ext4 and boot partitions are mounted in chroot) would have restored bootlloader to usable glory.

if unplugging Ubuntu and Solus boots then you are in business.
if it did not, maybe chroot again to be sure. Even if Ubu destroyed /boot files in Solus the chroot should've salvaged them.

elfprince destroying Solus install etc a last thing

If it turns out that you need to reinstall Solus, you'll have lots of company to comiserate with. In fact, I had to do it recently. At least, Solus is very quick and easy to install. And if you plan to modify partitions, why not include a 16 GB swap partition along with your boot partition? Then you'll not only be able to use EFI, but also hibernate. Might as well make the maximum improvement if you're going to do that at all.