Comment 4 for bug 2031253

I manually ran the command in the final error message, that is:
python3.10 -m curtin -vvv --showtrace -c /var/log/installer/curtin-install/subiquity-partitioning.conf install cp:///tmp/tmp8qst_wz0/mount
I didn't bother with all the environment variables or the log settings. Environment variables are already set in the shell that you get dropped into after the installer crashes. I redirected stdout and stderr to a file, and I have attached that file here. It appears that the partitioning actually works fine but when Subiquity attempts to do some apt work, it brings in the cdrom repo.

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Running in chroot, ignoring command 'start'
Get:1 file:/cdrom jammy InRelease
Ign:1 file:/cdrom jammy InRelease
Get:2 file:/cdrom jammy Release
Err:2 file:/cdrom jammy Release
  File not found - /cdrom/dists/jammy/Release (2: No such file or directory)
Hit:3 https://repo.saltproject.io/salt/py3/ubuntu/22.04/amd64/latest jammy InRelease
Get:4 http://security.ubuntu.com/ubuntu jammy-security InRelease [110 kB]
Hit:5 http://archive.ubuntu.com/ubuntu jammy InRelease
Get:6 http://archive.ubuntu.com/ubuntu jammy-updates InRelease [119 kB]
Get:7 http://archive.ubuntu.com/ubuntu jammy-backports InRelease [109 kB]
Reading package lists...
E: The repository 'file:/cdrom jammy Release' no longer has a Release file.
try 0: command ['apt-get', '--quiet', '--option=Acquire::Languages=none', '--option=Dir::Etc::sourcelist=/tmp/tmpbkroxt02/sources.list', '--option=Dir::Etc::sourceparts=/tmp/tmpbkroxt02/sources.list.d', 'update'] failed, rc: 100
Running command ['unshare', '--fork', '--pid', '--', 'chroot', '/target', 'apt-get', '--quiet', '--option=Acquire::Languages=none', '--option=Dir::Etc::sourcelist=/tmp/tmpbkroxt02/sources.list', '--option=Dir::Etc::sourceparts=/tmp/tmpbkroxt02/sources.list.d', 'update'] with allowed return codes [0] (capture=False)
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Perhaps this is a red herring. Maybe it doesn't do this when an encrypted partition is defined, but I am unsure how I would go about testing that.