juju needs to support systemd for >= vivid

Systemd support is currently under development, primarily to support CentOS: http://reviews.vapour.ws/r/671/

(I should have added: but will support Ubuntu, with a couple of minor adjustments)

We have frozen juju 1.22. We expect it to ship with vivid. This feature will need to be back-ported. How does Ubuntu feel about adding a feature to 1.22.1? If this is bad, then we will wait for 1.23 to be backported to w, v and t.

Feature freeze isn't until Mid-February, so any new feature can be put into the vivid package without problems by then. Even after that this will certainly get a freeze exception as this is a release goal. But as this apparently blocks OpenStack deployment/testing (said James Page), we'd probably backport this before feature freeze once it lands in trunk.

Looking at http://reviews.vapour.ws/r/671/ it looks very bad.

Please use DBus api to talk to systemd.

Or use golang-go-systemd-dev to operate against systemd.

Right now we (juju core) are scoping out the effort to add systemd support to juju in time for the feature freeze. We'll update here as we move forward.

Note that, as Andrew said, we have some of the work done already (though not merged yet). It's likely the trickiest part, so the remainder of the work should be of the add-systemd-support-wherever-we-support-upstart variety. Also note that our upstart configs are dynamically generated.

We've landed a patch for systemd support in juju. We are currently working through a couple of minor bugs before calling it good.

@Eric,

Thanks for the comment. To confirm is this still on track for 1.23 and the Ubuntu 15.04 (Vivid) release?

-thanks,
Antonio

the last of the patches to add systemd support in juju (including on vivid) has landed. There are a couple of caveats we need to look into though:

* vivid LXC containers on non-vivid hosts don't work correctly out of the box. This has an impact on local provider (I've been testing in a vivid KVM). See https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1347020
* vivid (and later) may be configured to boot with upstart (e.g. after an upgrade?). We are looking at adding a feature flag to support that use case (which I expect will be an uncommon one).

It will also be worth looking into the impact of systemd on existing charms that get published for vivid.

We have 1.20.14 in Vivid at the moment, and dep8 tests are now failing. I believe this is because the systemd switch has happened, and it cannot find upstart.

Which upstream release are you expecting us to pull in to Vivid to fix this please?

> Which upstream release are you expecting us to pull in to Vivid to fix this please?

As Juju has a "newer versions allowed" exception even for stables, that should equally apply to the current development series. So while I'm not officially in ~ubuntu-release, I'd say "whichever one works" is an acceptable answer? (Not sure whether I misunderstood the question)

Thanks Robie for the summary. For the record, if you want to continue running the DEP-8 tests in an upstart environment under vivid, you can do that at the top of your test:

if [ -d /run/systemd/system ]; then
    if [ ! -x /tmp/autopkgtest-reboot ]; then
        echo "SKIP: testbed does not support reboot"
        exit 0
    fi
    if [ -n "${ADT_REBOOT_MARK:-}" ]; then
        echo "SKIP: Reboot with upstart still runs systemd; using init= ?"
        exit 0
    fi
    echo "Installing upstart..."
    apt-get install -y upstart
    echo "Rebooting into upstart..."
    /tmp/autopkgtest-reboot b1
fi

(That's what I put into systemd-shim's tests, which also only run under upstart)

I also don't understand why this is marked Fix Released, upstream I only see systemd/centos support and no systemd/ubuntu support. I see code that assumes ubuntu == upstart.

https://github.com/juju/juju/commit/2ae93fe45df4b95bedf493adc07ee7049859fb2d also has some serious deficiencies, see Dimitri's comments.