Encrypted btrfs, which is my boot device for grub-install?

General discussions
1

Hi,

first-time user. Hope my question is not too stupid.

I have Debian Trixie, encrypted nvme-SSD with btrfs. Want to migrate from mini-pc to notebook.

I booted with findroot which prompted for disk password and correctly showed all partitions. Please make it also look for @rootfs/sbin/init. And please mention in the manual step list for grub-install that /boot/efi might also have its own partition and must also be mounted after doing chroot.

Below is my list of partitions. I used /dev/nvme0n1 for grub-install, but the result was nil: the new system did not see anything bootable, but the old system still booted. So - before I destroy too much: Which partition should I give grub-install?

~# lsblk | grep -v loop
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINTS
nvme0n1                259:0    0   1,8T  0 disk  
├─nvme0n1p1            259:1    0   976M  0 part  /boot/efi
├─nvme0n1p2            259:2    0   977M  0 part  /boot
└─nvme0n1p3            259:3    0   1,8T  0 part  
  └─nvme0n1p3_crypt    253:0    0   1,8T  0 crypt 
    ├─reise--vg-root   253:1    0   1,7T  0 lvm   /
    └─reise--vg-swap_1 253:2    0  31,6G  0 lvm   [SWAP]
2

It depends if your computer is running in Legacy BIOS mode or UEFI mode. You can verify by checking if /sys/firmware/efi exists on your Linux system. If it exists then you are running in UEFI mode otherwise your are in legacy BIOS mode. You use grub-install with a partition target in BIOS mode. With UEFI, the grub command to install the boot loader looks like this:
grub2-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=Linux --recheck
Also you can use the efibootmgr command on UEFI systems to show or update the boot entries in your firmware (grub-install can create such entries). This is what the firmware uses to determine where to find grub or whatever boot loader you use for your operating system which is normally stored in /boot/efi which is a small fat partition on your disk.

3

It is grub-install on debian trixie. I executed your command, went thru without error. I already did that before, just with fewer arguments.

But I still cannot boot. I placed an “echo” in cryptroot script, no I repeatedly get “I am local-block/cryptroot” until timeout. I should be asked for the passphrase - your findroot option does ask, but direct boot does not.