I am currently running Chimaera and wish to upgrade to Daedalus.

While I know that it should be perfectly safe to change the lines in my
sources.list from Chimaera to Daedalus, then run apt update, apt upgrade
and apt dist-upgrade, I also know that sometimes this does not go well. 
I was a Debian user, up until Buster.  When I couldn't get Buster to
work without systemd I said it was time to switch.  I have been using
Devuan ever since.  There were times when an upgrade did not go as
smoothly as it should have.

That being the case, when a new release comes out, I copy the entire
system to a new set of partitions, get that booting, and then upgrade
the copy.  That way, I still have the previous release still bootable in
case something goes wrong.

I have modified /etc/fstab in the copy, and modified and run lilo from
the original Chimaera.  When I try to boot to the copy of Chimarea,
however, I get a kernel panic when it tries to mount /usr.  It says the
file can not be found.  This sounds to me like /dev is not populating. 
On my current Chimaera system, /dev, /sys, /proc, and a few others have
filesystems mounted on them without needing anything in /etc/fstab:

These are all mounted:

sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs
(rw,nosuid,relatime,size=12203172k,nr_inodes=3050793,mode=755)
devpts on /dev/pts type devpts
(rw,nosuid,noexec,relatime,gid=5,mode=600,ptmxmode=000)
tmpfs on /run type tmpfs
(rw,nosuid,nodev,noexec,relatime,size=2459476k,mode=755)

without any reference in /etc/fstab.

This is /etc/fstab in the copy, and, yes, everything is on lvm:

# /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>
# / was on /dev/sda1 during installation
/dev/mapper/vg1-root--daedalus               / ext4    errors=remount-ro 0 1
/dev/mapper/vg1-boot                      /boot ext4    defaults   
0       2
/dev/mapper/vg1-tmp--daedalus              /tmp ext4    defaults   
0       2
/dev/mapper/vg1-var--daedalus               /var ext4    defaults   
0       2
/dev/mapper/vg1-usr--daedalus               /usr ext4    defaults   
0       2
/dev/mapper/vg1-usrlocal                    /usr/local ext3   
defaults    0       2
/dev/mapper/vg1-photos                    /usr/local/photos ext3   
defaults    0       2
/dev/mapper/vg1-vdisks                     /usr/local/vdisks ext3   
defaults    0       2
/dev/mapper/vg1-home                      /home ext4    defaults   
0       2
/dev/mapper/vg1-swap                     none swap    sw        0       0

/dev/sr0                                     /media/cdrom0 udf,iso9660
user,noauto 0       0


What do I need to do to have the above filesystems mounted and
populated, so that the system will boot?


Marc