It's Easy To Switch Between Upstart & Systemd Right Now On Ubuntu 15.04

While Ubuntu 15.04 is working towards migrating over to using systemd by default, it's still using Upstart at present. However, both Upstart and systemd are installed by default with current Ubuntu 15.04 builds.

For those that haven't yet tried out recent builds of Ubuntu 15.04, it's very easy to try out systemd and switch between that and Upstart. On Ubuntu 14.10 it was possible to experiment with systemd by installing its packages but now with the Vivid Vervet it's installed by default. Until making the default switch, Ubuntu 15.04's GRUB2 configuration has a kernel option for the stock boot parameters (using Upstart) and then an alternative one using systemd. So from GRUB2's menu you can simply switch between Upstart and systemd. The systemd option just appends init=/lib/systemd/systemd to the kernel command-line.

At the moment in the Ubuntu 15.04 archive is the systemd 218 package. Of course, most of the systemd work is shared with Debian.

Booting Ubuntu 15.04 with systemd is easy and has been trouble-free with the systems I've tried thus far. You can learn more about systemd on Ubuntu via this Ubuntu Wiki page.