On Feb 4, 2013 10:31 AM, "Lennart Poettering" <<a href="mailto:lennart@poettering.net">lennart@poettering.net</a>> wrote: > > On Fri, 01.02.13 12:50, Jake Edge (<a href="mailto:jake@lwn.net">jake@lwn.net</a>) wrote: > > > [ OK, let's try this again ... since I'm impatient about it sitting in > > the moderator queue, I went ahead and joined up ] > > > > Hi Lennart (and the rest of the systemd gang), > > > > I was quite surprised by some behavior that I found today in Fedora 18, > > which I think comes from systemd. I was trying to play with mount > > namespaces and was rather surprised to find that they didn't work as > > expected. After some googling, I realized that Fedora makes / a shared > > mount by default. That appears to come from: > > > > <a href="http://cgit.freedesktop.org/systemd/systemd/commit/?id=b3ac5f8cb98757416d8660023d6564a7c411f0a0">http://cgit.freedesktop.org/systemd/systemd/commit/?id=b3ac5f8cb98757416d8660023d6564a7c411f0a0</a> > > > > where you say: > > > > Setups which prefer the default of "private" should undo this change > > via invoking "mount --make-private /" or a similar command after boot. > > > > I am not sure that I want the default to be "private", but if I did, > > what is the proper, systemd-ish way to do so? > > Drop a unit file like this one to /etc/systemd/system/make-shared.service: > > [Unit] > Description=I like my hierarchies private > DefaultDependencies=no > Conflicts=shutdown.target > Before=local-fs-pre.target shutdown.target > > [Service] > Type=oneshot > RemainAfterExit=yes > ExecStart=/bin/mount --make-rprivate / > > And then pull this into the early boot: > > # mkdir -p /etc/systemd/system/local-fs.target.wants/ > # ln -s ../make-shared.service /etc/systemd/system/local-fs.target.wants/ > > I didn't test this, but it should do the job, nicely. > > Explanations: > > As this is an early boot process we need to disable the default > ordering/requirement dependencies systemd adds to services via > DefaultDependencies=no. Then, we order ourselves before > "local-fs-pre.target", which has the benefit that we can be sure that > further mounted fs will inherit the flag nicely and > race-freely. local-fs-pre.target is ordered after all local mounts. *before*? > We also order ourselves relative to shutdown.target, which ensures this > unit is stopped at shutdown. This is just to make things nice, and > actually has very little effect, as the unit doesn't do anything anyway > when stopped. > > We use Type=oneshot since the specified command should be executed at > boot and be waited for before boot progresses (adhering to the ordering > dependencies expressed in [Unit]). > > We use RemainAfterExit=yes so that the unit stays around after it is > started, so that we can easily check after boot if it got properly > started during boot. > > Finally, the ln -s line makes sure the unit is activated as part of > local-fs.target, which is where all local file system units tend to be > pulled in. > > Hope this makes sense! > > Lennart > > -- > Lennart Poettering - Red Hat, Inc. > _______________________________________________ > systemd-devel mailing list > <a href="mailto:systemd-devel@lists.freedesktop.org">systemd-devel@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/systemd-devel">http://lists.freedesktop.org/mailman/listinfo/systemd-devel</a>