From 8ea48dfcd33e8db0c01bf8c57c3bbcfdc3c86d4b Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 13 Jun 2014 12:43:49 +0200 Subject: update-done: add minimal tool to manage system updates for /etc and /var, if /usr has changed In order to support offline updates to /usr, we need to be able to run certain tasks on next boot-up to bring /etc and /var in line with the updated /usr. Hence, let's devise a mechanism how we can detect whether /etc or /var are not up-to-date with /usr anymore: we keep "touch files" in /etc/.updated and /var/.updated that are mtime-compared with /usr. This means: Whenever the vendor OS tree in /usr is updated, and any services that shall be executed at next boot shall be triggered, it is sufficient to update the mtime of /usr itself. At next boot, if /etc/.updated and/or /var/.updated is older than than /usr (or missing), we know we have to run the update tools once. After that is completed we need to update the mtime of these files to the one of /usr, to keep track that we made the necessary updates, and won't repeat them on next reboot. A subsequent commit adds a new ConditionNeedsUpdate= condition that allows checking on boot whether /etc or /var are outdated and need updating. This is an early step to allow booting up with an empty /etc, with automatic rebuilding of the necessary cache files or user databases therein, as well as supporting later updates of /usr that then propagate to /etc and /var again. --- units/.gitignore | 1 + units/systemd-update-done.service.in | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) create mode 100644 units/systemd-update-done.service.in (limited to 'units') diff --git a/units/.gitignore b/units/.gitignore index b8c0845956..45ddab72e8 100644 --- a/units/.gitignore +++ b/units/.gitignore @@ -65,6 +65,7 @@ /systemd-udevd.service /systemd-update-utmp-runlevel.service /systemd-update-utmp.service +/systemd-update-done.service /systemd-user-sessions.service /systemd-vconsole-setup.service /user@.service diff --git a/units/systemd-update-done.service.in b/units/systemd-update-done.service.in new file mode 100644 index 0000000000..dccb5137d2 --- /dev/null +++ b/units/systemd-update-done.service.in @@ -0,0 +1,21 @@ +# This file is part of systemd. +# +# systemd is free software; you can redistribute it and/or modify it +# under the terms of the GNU Lesser General Public License as published by +# the Free Software Foundation; either version 2.1 of the License, or +# (at your option) any later version. + +[Unit] +Description=Update is Completed +Documentation=man:sysusers.d(5) man:systemd-sysusers(8) +DefaultDependencies=no +Conflicts=shutdown.target +After=systemd-readahead-collect.service systemd-readahead-replay.service local-fs.target +Before=sysinit.target shutdown.target +RefuseManualStart=yes +RefuseManualStop=yes + +[Service] +Type=oneshot +RemainAfterExit=yes +ExecStart=@rootlibexecdir@/systemd-update-done -- cgit v1.2.3-54-g00ecf