[CentOS] Software RAID in CentOS (EL)

[James Olin Oden]

On 4/19/05, Francois Caen <frcaen at gmail.com> wrote:
> On 4/19/05, Joshua Baker-LePain <jlb17 at duke.edu> wrote:
> > If you want the system to survive losing a disk (i.e. it stays up until
> > you shut it down to swap the disk (if you don't have hot swap)), you
> > must RAID all partitions, including swap.  In a ks.cfg, it looks something
> > like this:
> 
> The reason I don't softraid1 my swaps is that the default behavior is
> striping a-la-raid0 if you have multiple swaps. At least that's my
> understanding of it.
> 
> You guys bring up a good point in case of drive failure. I never
> tested it. Do you guys know what happens if the swaps are not
> softraid1? Does the kernel panic or something of the like? Or does it
> survive and just operate on less swapspace?
> 
I only know that it continues along fine when swap is mirrored, but I
have never tested it without raided swaps.  We used to do this on
Solaris, so when we went to Linux we did the same thing.  That said I
would imagine that bad things would happen if you happened to have
pages swapped out.  Whats the kernel going to do when it goes to
aquire a page from disk (data or text) and its not available.  I would
hope it would panic, because something is very wrong in the
universe...james