powerdown restarts

[Paweł Brodacki]

2012/7/2 Richard Vickery <richard.vickeryrv at gmail.com>:
> On Mon, Jul 2, 2012 at 11:14 AM, Joe Zeff <joe at zeff.us> wrote:
> How do we boot up after "halt" or "sleep"? I quit using these commands years
> ago for lack of knowledge about booting back up. The man pages never gave me
> what I needed to know, and now that it has been brought up, I thought that I
> would ask and get my curiosity satisfied.
>
> Thanks.
>

I'm not using "sleep", but "halt" (stop the system, leave it powered
up) is very handy for systems with an UPS. On prolonged power loss UPS
will tell the system to halt, then wait a bit to give it time, then
cut the power. When sweet electricity starts flowing from the socket
in the wall once again, UPS gives power back to the system, which then
restores itself to the last power state, i.e. powered up. This results
in a nice boot and the machine is alive and kicking once again.

If the system was shut down, then it would just remain shut down after
power was restored.

Regards,
Paweł