Hi folks, I was recently doing a bunch of test reinstalls of Fedora [1], looking to see if it's complicated to retain the user directories during a reinstall. The answer is, sadly, that it's possible only with some manual tinkering. This is a known problem [2].
With a little bit of trickery, Anaconda will let the "home" subvolume be and install the system to a new "root" subvolume, so user data is preserved. But then after a reboot a new user will be created, because the old user is not hooked up into /etc/passwd. We actually have a partial solution for this: systemd-homed. With systemd-homed the information about the user is maintained in the user directory/subvolume/partition, e.g. /home/username.homedir. After a reinstall, ideally nothing needs to be done and the user account is ready to be used. The primary purpose of systemd-homed is to use per-user encryption using loopback devices. This still has various problem related to resizing and suspend. Work is being done [see 3,4 for recent developments], but it's not at a point where we can recommend it. But systemd-homed has a mode where the user "home" is just a normal directory or btrfs subvolume with some metadata stored in files [5]. Some work would be needed [6] to make this work smoothly, but it doesn't seem like too much. (Mostly filing down some rough edges in systemd-homed and adding pam_home_systemd and nss_systemd in various authselect profiles.) Thus the question: would this be something worth looking into? [1] https://discussion.fedoraproject.org/t/feedback-anaconda-web-ui-partitioning/108995/65 [2] https://discussion.fedoraproject.org/t/its-difficult-to-reformat-a-btrfs-partition-subvolume-in-the-installer/89052 [3] https://cfp.all-systems-go.io/all-systems-go-2024/talk/FFY3BB/ [4] https://www.youtube.com/watch?v=3e3IhBBU0JY [5] https://systemd.io/HOME_DIRECTORY/ [6] When I tested this today, this actually doesn't work. systemd-homed does a misguided check that break reinstalls. We'd need to figure out some solution here. Most likely just conditionalize that part of the code. Zbyszek -- _______________________________________________ devel mailing list -- devel@lists.fedoraproject.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
