hy im trying to install arch as the third os on my windows / ubuntu machine and i cant figure it out how to set the grub bootloader i have already read the friendly manual but probably also due to my non native English origins i coudnt find an answer to my question witch is during the arch install should i reinstall grub with grub-install ? i would prefer to keep the old (ubuntu) one also because its already customized but unfortunately i cant...if i dont install it i dont have the directory /boot/grub in witch i should place the grub.conf file so should i just create this directory ? i have tried with os-prober correctly activated to generate a new grub.conf but it doesnt pick up the arch install .., what are the files i must have to make grub recognize those partitions as a new os to witch assign a new boot entry ..
no like you can skip the entire grub-install part and just mount your ubuntu /boot partition as your boot partition in arch and go through the normal install process. then at the end, you just update the grub.cfg to include the arch install.
edit: if you don't have a separate ubuntu /boot partition, you're going to need to reinstall it with a separate boot partition, or configure the bootloader in arch and do grub-install but stick in the ubuntu boot block into grub.cfg. the issue is that you're still going to need to update the configuration on the ubuntu side so it uses the arch /boot partition and installs kernels there.
Thanks a lot man I would love to tell you I understand everything but unfortunately the only part that I got was the first and I don't have a separate boot partition :( so what do you mean by stick in the ubuntu boot block into grub config I have to reinstall grub from arch then I update it making a new .Cfg and then remaining in the arch install I should find and add the other two boot entries ? Should I delete grub before installing it again ? Im asking because I think I have already tried to install it and i believe I was still using the ubuntu one ... What about updating grub on the Ubuntu side how am I going to boot into it ? Thanks a lot man I don't want to waste your time u gave me some nice homeworks I will be back in a few days ...
no worries! you want a separate boot partition on your hard disk to make this all easier. if you don't have one already, I would make one, then go back through the arch install. at the end, there should be instructions on how to update the grub.cfg for arch. you'll need to do the exact same thing for Ubuntu. the only hard part is that Ubuntu is set up right now to not mount a /boot partition so when you install updates, the updated boot images won't get installed in the right place. so you need to boot into Ubuntu first and change /etc/fstab so it mounts the boot partition to /boot. then you need to run:
then you can go back and do the arch install with the same /boot partition and run grub-install. there's detailed instructions on how to change the boot partition here and the ArchWiki should have the rest.
Thank you so much it's like a couple of weeks I'm going back and forth on this topic and this is the biggest step I have done ... I will surely let you know if I successfully end up bricking my PC :)
Btw I'm sorry for any previous gender errors I have just noticed the correct pronouns 😅
not a problem! good luck!
Hey do you know if it's normal then after mounting the /boot partition, adding this ... UUID=1f32... /boot ext4 defaults 0 2 ... to the fatab and updating grub with grub-update or white grub mkconfig.io.... I can't no longer boot into Ubuntu ?it puts me in some kind of recovery mode Should I proceed anyway with the arch install ? Does the problem come from the fact I haven't already reinstalled grub ? PS I have tried the --refresh flag but apparently it doesn't exist ...
yeah, you need to run grub-install now, so do it from the arch install environment. you'll be able to boot into Ubuntu once that's done (assuming grub.cfg is properly configured for Ubuntu)
Thanks sis I have done that unfortunately I'm back to the start when booting up I have the customized grub witch makes me think I'm using ubuntus grub and since I have added the line to the fstab I'm booted straight into emergency mode I have typed as suggested journalctl -xb to see the complete logs but there's like 2840 something lines I have scrolled and nothing gives me a hint of what's happening I believe I already had an integrity problem loading x.509 certificate -65 I have taken some pictures of warnings and errors let me know if it would be helpful to you ...
I have used this guide for the rest but I have checked and it matches with the arch wiky https://www.learnlinux.tv/arch-linux-full-installation-guide/ I have chosen to encrypt my LVM partitions and I have modified the files accordingly ...(I hope ) Apparently something is wrong before the description part because I don't see any prompt asking me for the password ... Hope you could help me
Btw since it was working I haven't touched the grub.conf in Ubuntu I have previously added the encryption lines on it because i was confused about what grub.conf file will end up needing to decrypt, and I was scared of not being able to boot back... it doesn't seem to give any problem back then so I won't blame this on it but I will defenetly revert it back to default and give it another go ...
Update mounting the /boot partition manually while in recovery allows me to boot into Ubuntu still no sign of the arch install thow (yes I have the os-prober flag ser up ) with ubuntu I can see also windows but not arch and from arch I can see neither ubuntu and windows I have also tried to modify the line in the fatab as follows with no results ... Should I somehow activate or validate the new fstab ?
UUID=1f32... /boot ext4 errors=remount-ro 0 1
bit tired to respond tonight - I'll get back to you in the morning
No problem it's really late here too