Subject: Re: bug#40999: GRUB prevents booting a degraded RAID1 array atop LUKS

From: Maxim Cournoyer <[email-masked]>
Date: Sat, 07 Aug 2021 01:06:58 -0400

Hello,

[email-masked] writes:

> On a system where:
>
> 1) Each disks comprising the array is fully LUKS encrypted
> 2) Each mapped disk is made part of a Btrfs RAID1 array
>
> When attempting to boot the system after pulling out (in BIOS or using
> the cable) the drive to simulate a complete disk failure, GRUB hangs,
> prompting for the LUKS password of the disappeared drive and
> (unsurprisingly) failing to open it.
>
> This prevents booting in a degraded LUKS encrypted, Btrfs RAID1 on Guix
> System.

I retested this today, and the problem still occurs.  Here's a
screenshot from the failed boot (GRUB):

Ideally, GRUB (or is it our boot script?) should be smart enough to
realize that oh, that's Btrfs RAID1, it ought to work in degraded mode,
so let's keep going.

Thanks,

Maxim