A number of folks have asked about this in #fedora over the last few months, so I thought I would do a quick blog post about rc.local in the systemd world.

/etc/rc.d/rc.local is no longer shipped, but it still works fine once you set it up correctly:

Create /etc/rc.d/rc.local as root.
Add a “#!/bin/sh” to the top of it.
chmod 755 /etc/rc.d/rc.local

Once you do those things, systemd will see the file exists, is executable, is a shell script and will run it. No further action needed.
I do hope systemd maintainers keep this functionality around as it’s sometimes handy to run things in a simple script rather than create a new unit file for it.