[SWLUG] UPS etc

[Telsa Gwynne]

On Wed, Jun 09, 2004 at 12:02:17PM +0100 or thereabouts, Rhys Sage wrote:
> After a slight power glitch the other day, it came to
> my attention that a UPS might be useful to have -
> particularly since it adversely affects XP more than
> any other O/S I've ever encountered.
> 
> How does a sudden power loss affect Linux? With XP I
> have to fiddle around reinstalling the modem each
> time.

Dunno, because I have a UPS :) 

More seriously, sudden power losses used to affect Linux badly in
the days when ext2 was the standard file system. After a power
loss or hitting the big red button, it was common to be faced
with fsck (actually e2fsck, I think?) prompts on bootup saying
"the file system is messed up; shall I fix it for you?" SuSE even
used to print the fsck manual page in their printed manuals, just
in case you needed it (since man would not be available if you
met this).

So everyone went to work on journalling file systems which are
much more blase about the power vanishing: ext3, xfs, reiserfs
and the one I forget. 

If you are still using ext2, then you will have these problems.
If you have a journalling file system, you are much less likely
to end up with a trashed filesystem which requires fixing. 
Although I gather it can still happen.

What we find is that the Linux boxes in the house (the ones not
on UPSes) are fine: they come back up after the power goes off
and back on again.

The cablemodem thingy gets upset, though, and has to be switched
off and on again. 

Telsa