Recently, the cryptsetup scripts have changed from an ext2 to an ext4 default filesystem for the tmp option in crypttab.  d-i only allows ext2 or swap for an encrypted volume with a /dev/urandom key.  This is causing the fstab to try and mount tmp as an ext2 volume, when it has been formatted as ext4.  It fails.

A possible fix might be to specify tmp=ext2 in the crypttab options instead of just tmp.

I see, I wasn't aware of that.
When executing update-initramfs -u in a chroot via a live CD, I get:

update-initramfs: Generating /boot/initrd.img-3.16.0-4-amd64
cryptsetup: WARNING: could not determine root device from /etc/fstab
Warning: /sbin/fsck.btrfs doesn't exist, can't install to initramfs,
ignoring.
<perl locale warnings>

More details of the setup are described in the following mailing list
message (please ignore issue #1), including fstab, crypttab contents and
blkid output:
https://lists.debian.org/debian-user/2015/02/msg00323.html

(please excuse the use of '<etc>' in the UUID's, I couldn't be bothered
to type them all out in full)

The filesystem after installation does contain an install of cryptsetup,
just no copy in initrd. I added 'cryptsetup' into the
/etc/initramfs-tools/modules file before executing update-initramfs -u,
resulting in the above output, and no cryptsetup binary or config files
present in the /boot initrd image.
I'm not going to dispute whether the fault lies with initramfs-tools or
partman-crypto, because I don't have a clue.

All I know at this time is that comparing two VM installs, one using
luks + btrfs and one using luks + ext4, otherwise identical, the btrfs
one lacks cryptsetup in its initrd after installation, causing boot
failure, while the ext4 one is fine, and using a live CD + chroot to try
to fix things via update-initramfs, the tool runs fine on the ext4
install, but fails on the btrfs install. I am guessing that both
problems have a common cause.

Thank you for taking some time to respond to my issue. I appreciate any
help you can offer in resolving it.

Dear Maintainer,

I installed debain with encrypted hard disk. The /tmp directory is mounted to
a separate partition with a random key. In /etc/crypttab the line

    sda3_crypt /dev/sda3 /dev/urandom cipher=aes-xts-plain64,size=256,tmp

was generated, in /etc/fstab the line

    /dev/mapper/sda3_crypt /tmp            ext2    defaults        0       2

was generated. During boot I got the message

    Mounting local filesystems...mount: wrong fs type, bad option, bad
    superblock on /dev/mapper/sda3_crypt,
    missing codepage or helper program, or other error
    [...]

And indeed, the /tmp file system was not mounted. According to crypttab(5), I
changed the corresponding line in /etc/crypttab to

    sda3_crypt /dev/sda3 /dev/urandom cipher=aes-xts-plain64,size=256,tmp=ext2

Now the /tmp file system is mounted on boot as expected.


It seems to me that the original crypttab entry is either invalid (as the
option 'tmp' needs to be followed by '=<tmpfs>') or the default file system for
tmp is not ext2.

For the sake of completeness I append /etc/crypttab and /etc/fstab. The only
manual change I have made is the above mentioned line in crypttab.

Thank you for the (otherwise) really great automated installation process.

Sincerely
Lars
--- /etc/crypttab ------------------------------------------------------------

sda2_crypt UUID=afc745bf-6b36-4f43-a483-b49d28ab7eea none luks
sda3_crypt /dev/sda3 /dev/urandom cipher=aes-xts-plain64,size=256,tmp=ext2
sda5_crypt /dev/sda5 /dev/urandom cipher=aes-xts-plain64,size=256,swap

--- /etc/fstab ---------------------------------------------------------------

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
/dev/mapper/sda2_crypt /               ext4    errors=remount-ro 0       1
# /boot was on /dev/sda1 during installation
UUID=04d34b71-b02b-4f10-8a04-d399793a087c /boot           ext4    defaults        0       2
/dev/mapper/sda3_crypt /tmp            ext2    defaults        0       2
/dev/mapper/sda5_crypt none            swap    sw              0       0
/dev/sr0        /media/cdrom0   udf,iso9660 user,noauto     0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto  0       0