As suggested by Bill Nottingham: rc.local is often used for frobbing the
network.
https://bugzilla.redhat.com/show_bug.cgi?id=754789
# systemd-rc-local-generator if /etc/rc.d/rc.local is executable.
[Unit]
Description=/etc/rc.d/rc.local Compatibility
# systemd-rc-local-generator if /etc/rc.d/rc.local is executable.
[Unit]
Description=/etc/rc.d/rc.local Compatibility
# systemd-rc-local-generator if /etc/init.d/boot.local is executable.
[Unit]
Description=/etc/init.d/boot.local Compatibility
# systemd-rc-local-generator if /etc/init.d/boot.local is executable.
[Unit]
Description=/etc/init.d/boot.local Compatibility