install.py crashed with AssertionError in __init__(): Failed to mount the target: /target

[ulrich]

standart install with zfs and encryption

ProblemType: Crash
DistroRelease: Ubuntu 21.04
Package: ubiquity 21.04.14
ProcVersionSignature: Ubuntu 5.11.0-14.15-generic 5.11.12
Uname: Linux 5.11.0-14-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu62
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.461
Date: Mon Apr 26 21:40:11 2021
ExecutablePath: /usr/share/ubiquity/install.py
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed maybe-ubiquity quiet splash ---
InterpreterPath: /usr/bin/python3.9
LiveMediaBuild: Ubuntu 21.04 "Hirsute Hippo" - Beta amd64 (20210415)
ProcCmdline: /usr/bin/python3 /usr/share/ubiquity/install.py
Python3Details: /usr/bin/python3.9, Python 3.9.4, python3-minimal, 3.9.4-1
PythonArgs: ['/usr/share/ubiquity/install.py']
PythonDetails: N/A
SourcePackage: ubiquity
Title: install.py crashed with AssertionError in __init__(): Failed to mount the target: /target
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: N/A

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Chris McDonough (chrism-plope)]

This symptom is back in today's daily build of 22.04 when attempting to install to ZFS/zsys with encryption. I was able to install to ZFS/zsys without encryption successfully.