rpm-ostree/docs
Colin Walters d2bd8500da compose: Add tmp-is-dir option to make /tmp a directory
There are a few reasons to do this. First, systemd changed to refuse mounts on
symlinks, and hence if one *wants* "/tmp-on-tmpfs", one would need to write a
different `sysroot-tmp.mount` unit.

Second, the original rationale for having this symlink was that if you had
multiple ostree stateroots ("osnames"), it's nicer if they had the same `/tmp`
to avoid duplication. But in practice today that's already an issue due to
`/var/tmp`, and further the multiple-stateroot case is pretty unusual. And that
case is *further* broken by SELinux (if one wanted to have e.g. an Ubuntu and
Fedora) stateroots.  So let's fully decouple this and make `/tmp` a plain
old directory by default, so systemd's `tmp.mount` can become useful.

Now, things get interesting for the case where someone wants a physical `/tmp`
that *does* persist across reboots. Right now, if one just did a `systemctl mask
tmp.mount` as we do in Fedora Atomic Host's cloud images, you'd get a semantic
where `/tmp` stays per-deployment, which is weird.  Our recommendation for
that should likely be to set up a bind mount for `/tmp` → `/var/tmp`.

For now, this stays an option to ensure compatibility; if FAH Cloud images
want to stay with "physical /tmp", then we'd have to change the kickstart.

Closes: https://github.com/projectatomic/rpm-ostree/issues/669

Closes: #778
Approved by: jlebon
2017-05-24 17:49:36 +00:00
..
manual compose: Add tmp-is-dir option to make /tmp a directory 2017-05-24 17:49:36 +00:00
CONTRIBUTING.md docs: fix ostree and CONTRIBUTING.md links 2016-07-12 15:46:53 +00:00
index.md docs: update linked project names and minor tweaks 2017-05-15 15:47:39 +00:00