Re: Debian 11 couldn't determine device type, assuming default (plain)

[David Christensen <dpchrist@holgerdanske.com>]

On 1/29/22 22:15, David Christensen wrote:
> debian-user:
>
> I have:
>
> 2022-01-29 22:09:45 dpchrist@laalaa ~
> $ cat /etc/debian_version ; uname -a
> 11.2
> Linux laalaa 5.10.0-11-amd64 #1 SMP Debian 5.10.92-1 (2022-01-18) x86_64 
> GNU/Linux
>
>
> It has encrypted swap (and root), created by the Debian installer.
>
> 2022-01-29 22:14:17 dpchrist@laalaa ~
> $ grep sdb2 /etc/crypttab
> sdb2_crypt /dev/disk/by-partuuid/544032f5-02 /dev/urandom 
> cipher=aes-xts-plain64,size=256,swap,discard
>
>
> When I boot and enter the root passphrase, I see the following warning 
> anywhere from two to a dozen or more times:
>
> cryptsetup: WARNING: sdb2_crypt: couldn't determine device type, 
> assuming default (plain)
>
>
> What is causing the warning?
>
>
> How do I fix whatever is causing problem(s), so that no warning is 
> displayed?
>
>
> David


This appears to be the result of the Debian installer assuming that 
everyone uses suspend/ resume and the suspend image is stored in the 
swap partition.


One work-around is to edit /etc/default/grub to disable resume:

GRUB_CMDLINE_LINUX="noresume"


It also appears that the GRUB settings are stored in two or more places 
-- text configuration files and binary files -- and the binary files 
must be rebuilt whenever the setting change:

# update-grub
Generating grub configuration file ...
Found background image: /usr/share/images/desktop-base/desktop-grub.png
Found linux image: /boot/vmlinuz-5.10.0-11-amd64
Found initrd image: /boot/initrd.img-5.10.0-11-amd64
Found linux image: /boot/vmlinuz-5.10.0-10-amd64
Found initrd image: /boot/initrd.img-5.10.0-10-amd64
done


David