I just set up a custom systemd target on my laptop for the first time using  to split out services that I don't want running if I'm on a public wifi. I configured things so that by default, I boot into a custom 'home.target' which starts everything up, and then if I'm on an untrusted network I can `systemctl isolate multi-user` to bring down httpd, mysqld, sshd, and anything else I'd rather not have listening to outside traffic.
Usually under those circumstances, my SSID wouldn't be available and email@example.com would have failed, so in an effort to automate the process I added the following to the netctl service file and did `systemctl --system daemon-reload` to read in the changes.
The end result is that if systemd is unable to start firstname.lastname@example.org, it will isolate the multi-user target, thus shutting down httpd, mysqld, sshd, and other services belonging to home.target.
I'm just posting this because the solution wasn't obvious and a google search for the terms in the subject of this email didn't turn up anything about OnFailure and OnFailureIsolate. Hopefully the info will be useful to someone else.
I also wouldn't mind feedback on this setup. Is what I'm doing sane? Could it be done better? My full home.target and email@example.com are linked below .