= Ubuntu Server installs = There used to be minimal installers and a python commandline utility to build KVM images. Not Enterprise enough, I suppose. There is still a minimal ISO, hidden away: * 20.04: http://archive.ubuntu.com/ubuntu/dists/focal/main/installer-amd64/current/legacy-images/netboot/mini.iso = Notes on chroot'ing from SystemRescueCD or the like = You can mount it like so: ``` lang=bash # Mounting a classic MBR/Legacy install sudo mount /dev/sda1 /mnt # Or, mounting a UEFI install, you may find the first partition is actually an EFI partition rather than your root. So instead it's more like: sudo mount /dev/sda2 /mnt sudo mount /dev/sda1 /mnt/boot/efi # Either way, then mount all the devices from the live session sudo mount --bind /dev /mnt/dev sudo mount --bind /dev/pts /mnt/dev/pts sudo mount --bind /proc /mnt/proc sudo mount --bind /sys /mnt/sys # And now chroot into a shell in your existing install sudo chroot /mnt ``` But if you're fixing GRUB on an EFI system and have booted into SystemRescueCD (or a live Kubuntu USB or such) in UEFI mode you may then find that running `grub-install` returns ``` grub-install: warning: EFI variables cannot be set on this system. grub-install: warning: You will have to complete the GRUB setup manually. ``` You just need to run `grub-install --removable` to avoid that, having bootstrapped into this via EFI USB boot was how I got there myself certainly as per https://superuser.com/a/1749282

= Ubuntu Server installs = == Minimal installers == There used to be minimal installers and a python commandline utility to build KVM images. Not Enterprise enough, I suppose. There is still a minimal ISO, hidden away: * 20.04: http://archive.ubuntu.com/ubuntu/dists/focal/main/installer-amd64/current/legacy-images/netboot/mini.iso == Hide ESM rambling == `sudo touch /var/lib/update-notifier/hide-esm-in-motd` as per https://askubuntu.com/a/1509911/306954 = Notes on chroot'ing from SystemRescueCD or the like = You can mount it like so: ``` lang=bash # Mounting a classic MBR/Legacy install sudo mount /dev/sda1 /mnt # Or, mounting a UEFI install, you may find the first partition is actually an EFI partition rather than your root. So instead it's more like: sudo mount /dev/sda2 /mnt sudo mount /dev/sda1 /mnt/boot/efi # Either way, then mount all the devices from the live session sudo mount --bind /dev /mnt/dev sudo mount --bind /dev/pts /mnt/dev/pts sudo mount --bind /proc /mnt/proc sudo mount --bind /sys /mnt/sys # And now chroot into a shell in your existing install sudo chroot /mnt ``` But if you're fixing GRUB on an EFI system and have booted into SystemRescueCD (or a live Kubuntu USB or such) in UEFI mode you may then find that running `grub-install` returns ``` grub-install: warning: EFI variables cannot be set on this system. grub-install: warning: You will have to complete the GRUB setup manually. ``` You just need to run `grub-install --removable` to avoid that, having bootstrapped into this via EFI USB boot was how I got there myself certainly as per https://superuser.com/a/1749282

= Ubuntu Server installs = == Minimal installers == There used to be minimal installers and a python commandline utility to build KVM images. Not Enterprise enough, I suppose. There is still a minimal ISO, hidden away: * 20.04: http://archive.ubuntu.com/ubuntu/dists/focal/main/installer-amd64/current/legacy-images/netboot/mini.iso == Hide ESM rambling == `sudo touch /var/lib/update-notifier/hide-esm-in-motd` as per https://askubuntu.com/a/1509911/306954 = Notes on chroot'ing from SystemRescueCD or the like = You can mount it like so: ``` lang=bash # Mounting a classic MBR/Legacy install sudo mount /dev/sda1 /mnt # Or, mounting a UEFI install, you may find the first partition is actually an EFI partition rather than your root. So instead it's more like: sudo mount /dev/sda2 /mnt sudo mount /dev/sda1 /mnt/boot/efi # Either way, then mount all the devices from the live session sudo mount --bind /dev /mnt/dev sudo mount --bind /dev/pts /mnt/dev/pts sudo mount --bind /proc /mnt/proc sudo mount --bind /sys /mnt/sys # And now chroot into a shell in your existing install sudo chroot /mnt ``` But if you're fixing GRUB on an EFI system and have booted into SystemRescueCD (or a live Kubuntu USB or such) in UEFI mode you may then find that running `grub-install` returns ``` grub-install: warning: EFI variables cannot be set on this system. grub-install: warning: You will have to complete the GRUB setup manually. ``` You just need to run `grub-install --removable` to avoid that, having bootstrapped into this via EFI USB boot was how I got there myself certainly as per https://superuser.com/a/1749282