The 2000s called. They want their intro(8) back.

That manual page was last updated in 2006 and I think it needs a serious 
update.

At a minimum, I would add:
- sysrc(8) (and maybe rc.conf(5))
- sysctl(8) (and maybe sysctl.conf(5))
- whichever ZFS command(s) control mounting at boot
- automount(8) (and maybe auto_master(5) and autofs(5))
- service(8)
- https://docs.freebsd.org/en/books/handbook/partiii/ and maybe 
https://docs.freebsd.org/en/books/faq/#admin (or the split-HTML 
equivalent when it comes).

What else? Contrariwise, is anything in it no longer relevant?