TYPE is one of arch, plain, fai.
HOST is a hostname known to the dhcp server, or default for all, or none to disable
--r Don't redeploy fai config.
+-r Don't redeploy fai config. For example, if there is a different host
+ that is mid-install.
-a Wait for 2 dhcp acks, then disable the pxe server after a delay.
First ack is for pxe boot, 2nd ack is for os boot. Sometimes
on debian, there is a 3rd one shortly after the 2nd. I can't remember