Shutting of manually causes damage?

V!NCENT · 08-31-2006, 05:07 PM

I was reading Introduction to Linux - hands on guide from the LDP. There was this line saying:

Quote:

While Linux was not meant to be shut off without application of the proper procedures for halting the system, hitting the power button is equivalent to starting those procedures on newer systems. Ihowever, powering off an old system without going through the halting process might cause severe damage!

I would like to know why it is wrong to manualy shut down a computer. What damage does it causes(hardware, software or both?)?

crazyjimbo · 08-31-2006, 05:14 PM

I think the main issue is that if there is some data in buffer that has only been half written to a physical drive and you shut it off before it is all written, you will lose data. It could be a case of losing that file, or worse, corrupting the whole filesystem and losing all the data! When you tell a computer to shutdown, it will clear all the buffers and finish writting everything to disk before powering off.

V!NCENT · 08-31-2006, 05:18 PM

Is there any chance of damaging the hardware?

jschiwal · 08-31-2006, 05:31 PM

The quote is alluding to ACPI systems where pressing the power button momentarily sends a signal to power down. So in that case you are executing the inittab's shutdown procedure which probably is "/sbin/shutdown -h now".