[LBo] chapter 2 , how to shut down

[Stefan Waidele]

Steve Kist schrieb:
> Rafi Gabzu wrote:
> 
>> 1.Assuming I'm in the text mode , how do I shut down / halt the system
>> before powering it off ?
> $> shutdown -h now - see man shutdown

Many systems also have a "poweroff" command, which does basically the same.

>> 2.How can I protect my self from a sudden electrical power off ?
> UPS

Or use a laptop :)

In case an UPS (Uninteruptible Power Supply) is too expensive, you might 
take a look at journaling filesystems (ext3, reiser, xfs?).

If poweoff occurs during a write to disk, a clean state can be reached 
when the system goes up the next time. The filesystem will not be 
corrupted by interrupted write-operation.

An UPS can save you from loosing the data you are working on when power 
dies. But be aware that an UPS needs care.
I removed my UPS from my _server_ in the hotel because I had three 
failures due to old batteries in the UPS, but NO power-outage since years!

But I am speaking against UPSs

>> 3. What kind of damage might happen ?
> Depends on what the box is doing at the moment, often none,
> except for a longer boot process as the file system is reviewed.

And you will lose the stuf you worked on since the last save.

Stefan