I normally use this command to restart my daemons(e.g. vsftpd):
$sudo /etc/init.d/vsftpd restart
Early today I noticed it said that I can try restart(8) utility. I did:
$sudo restart vsftpd
It worked. But when I tried to restart my apache2:
$sudo restart apache2
> restart: Unknown job: apache2
Why are they different? Of course I can restart apache2 by /etc/init.d/apache2