Arch Linux

faiden

Member

Registered: 2014-03-08

Posts: 22

[SOLVED]luks btrfs grub problem

Hi. I have a problem with installing Arch linux when following the guide: https://wiki.archlinux.org/index.php/Dm … _with_swap

My plan is to install this on a old laptop that does not have UEFI hence I did not create the UEFI (EFI) partition.
I'm currently trying it out on virtualbox

sda2 is going to be my encrypted swap

NAME          FSTYPE      LABEL       UUID                                 MOUNTPOINT                PARTUUID
sr0           iso9660     ARCH_201611 2016-11-01-11-13-14-00               /run/archiso/bootmnt     
loop0         squashfs                                                     /run/archiso/sfs/airootfs
sda                                                                                                 
├─sda2                                                                                               4c916a76-c012-47c9-a7ec-3fda44d1dc7c
└─sda1        crypto_LUKS             1ee3bafe-3c6d-4127-bd2f-1be636ac4d61                           b78c2f04-fa4c-4c04-aed3-b6af3c4bfb1b
  └─cryptroot btrfs                   3ce20d85-c5c7-4cb9-8157-65c928028b09 /mnt/.snapshot           

I get the follwing error message  when installing grub on a partitionless disk: https://wiki.archlinux.org/index.php/GR … nless_disk

grub-install: info: /dev/mapper/cryptroot is not present.
grub-install: info: guessed root_dev `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' from dir `/boot/grub/i386-pc'.
grub-install: info: setting the root device to `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61'.
grub-install: error: unable to identify a filesystem in hostdisk//dev/sda; safety check can't be performed.

After restart I get FATAL No bootable medium found! System halted.

So I tried the normal grub install:
grub-install --target=i386-pc /dev/sd1
and got No error reported but when creating the grub config it show me the error:

Generating grub configuration file ...
Found linux image: /boot/vmlinuz-linux
Found initrd image(s) in /boot: initramfs-linux.img
/usr/bin/grub-probe: error: disk `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' not found.
/usr/bin/grub-probe: error: disk `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' not found.
Found fallback initrd image(s) in /boot: initramfs-linux-fallback.img
/usr/bin/grub-probe: error: disk `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' not found.
/usr/bin/grub-probe: error: disk `cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' not found.
done

and on restart i get:

Grub Loading..
Welcome to GRUB!

error:  no such cryptodisk found.
error:  disk 'cryptouuid/1ee3bafe3c6d4127bd2f1be636ac4d61' not found.
entering rescue mode.

I tried setting my sda1 as bootable device (But now I cant open my LUKS device)

What am I doing wrong? Cant I have a BTRFS with encrypted boot and swap?

I have tried the guide serveral times now with the same outcome please help me

Last edited by faiden (2016-11-29 19:01:57)

faiden

Member

Registered: 2014-03-08

Posts: 22

Re: [SOLVED]luks btrfs grub problem

After some research I came to the conclusion that my problem was using a GTP partitioning scheme.

"For GRUB to boot from a GPT-partitioned disk on a BIOS-based system, a BIOS boot partition is required. Please note that this partition is unrelated to the /boot mountpoint, and will be used by GRUB directly. Do not create a filesystem on it, and do not mount it."

And I was not using a separate Boot partition.

However I did try the same guide but with MBR and it worked without problems.

I guess you cant get a encrypted boot partition in GTP unless you are going to use UEFI.