[CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Thu Feb 19 00:29:13 UTC 2009
Ray Van Dolson <rayvd at bludgeon.org>

On Wed, Feb 18, 2009 at 06:20:59PM -0500, Ross Walker wrote:
> On Feb 18, 2009, at 2:29 PM, Ray Van Dolson <rayvd at bludgeon.org> wrote:
> 
> > On Wed, Feb 18, 2009 at 11:12:13AM -0800, John R Pierce wrote:
> >> Scott Silva wrote:
> >>> You can make LVM over raid 1's in Disk Druid, but I don't think it  
> >>> will do
> >>> raid 10. And you cannot boot from software raid 5 (yet).
> >>>
> >>
> >> a LVM over several raid 1's is effectively raid10 as LVM will  
> >> stripe the
> >> volumes across the devices.   It would be nice if  LVM could do
> >> mirorring too (like LVM on AIX does) and was tighter integrated  
> >> with the
> >> file system tools (again, like LVM on AIX...  grow a LV and it  
> >> grows the
> >> JFS thats sitting on it, transparently and online).
> >>
> >
> > Can't Linux LVM do mirroring?  I swear I read that it could in the man
> > page.  Never have tried it however and you certainly can't set it up
> > from disk druid in anaconda.
> 
> Lvm can do mirroring, but of requires a third drive to do mirror  
> logging which  kind of defeats the whole raid1 concept, I guess if you  
> have a VG of a plethora of drives this is no biggie.
> 
> And besides grub still after all these years does not support booting  
> LVM volumes.
> 
> Jeez, you think with the Solaris folk able to boot off of ZFS now from  
> grub we'd have  the ability to boot off of LVM by now!

Hehe, I guess the fact that we can achieve fairly similar results using
md + LVM has made it a lower priority. :-/

Ray