Comment 5 for bug 1436956

I had an email conversation with Mr. Didier Roche (with CC to Mr. James Hunt, Upstart package maintainer) , who commited the change which moved files such as /sbin/init and /sbin/shutdown from upstart (1.13.2-0ubuntu10) to upstart-sysv (1.13.2-0ubuntu12):
http://changelogs.ubuntu.com/changelogs/pool/main/u/upstart/upstart_1.13.2-0ubuntu12/changelog

In his replies to my email, Mr. Roche mentioned that "Upstart is not anymore the init system by default on ubuntu 15.04, they switched to systemd by default a month ago."

When I told him that I encountered this bug when using the "Docker" Image from Online Labs (now Scaleway), he said that "They need to either use our own seed system to respect ubuntu-minimal defaults and not reinstall themselves what they need, but clearly, they need to install systemd-sysv starting from vivid as we don't support upstart for those use case anymore. They should just really use the ubuntu-minimal metapackage if they want to not get into those issues in the futures while following ubuntu do."

And when I asked about the possiblility of making Upstart depend on upstart-sysv, he replied: "That's the opposite goal of the change :) We want to have the upstart binaries so that someone can decide in grub to either boot systemd (default, as per systemd-sysv installed) or upstart. Both systemd-sysv and upstart-sysv installs the same files (symlinks) to decide what to boot, so they can't be installed altogether. We thus can't have upstart depending on upstart-sysv."