pci-e hardware raid controller

[vu pham]

On Tue, 2007-06-05 at 15:27 -0500, C M Reinehr wrote:
> >
> > There are two reasons:
> >
> > 1. this is a test system for coding and I would like to have the highest
> > disk access performance as much as possible, and I think the hardware
> > raid is faster than software raid. Or is the gain so small to afford a
> > hardware raid ?
> 
> 	I have absolutely no experience here, but if I had to guess, I would think 
> that a true, hardware based solution would, indeed, out perform a software 
> based solution. Whether the difference would be significant or not would 
> depend upon the load put upon the system.
> 
> > 2. With LVM, Linux will save the lvm configuration somewhere on disk and
> > to fully restore the whole system, you have to prepare a similar lvm
> > configuration in advance, right ? If I am only able to restore to a
> > single disk, will the restore work ? I 've tried LVM only one or twice
> > long time ago, so I think I am pretty much wrong on this.
> 
> 	This would depend upon your backup solution. As far as any applications would 
> be concerned, they would see only a single large partition. So, if you used 
> tar, Bacula or some other, similar backup program you would just be copying 
> files and could restore them anywhere that you chose. So, you could restore 
> to a single disk or multiple disks.
> 
> 	However, if you're talking about completely imaging the system, O/S & all, 
> I'm not sure just what problems you would run into. Personally, my procedure 
> is to backup my application files and my configuration files (/etc/*) and 
> then do a minimum, new system install, creating a new volume management 
> scheme, raid, etc. from scratch, and then restore my applications on top of 
> it. But then, I only have a half-dozen or so systems to worry about.
> 
> 	On the other hand, if your raid card should fail, you would have to replace 
> it with an identical card. Anything else and you still would not be able to 
> recover your disks. At least with LVM2 you're not restricted to any 
> particular hardware make, model, or hardware configuration.
> 
> 	For what it's worth, I use LVM2 on every new install, desktop or server. 
> Since you were speaking only of RAID0, you wouldn't need to do a RAID (md) 
> install. As I understand it, LVM2 can handle striping, itself.

I am going to give LVM a try. Everybody mentions it so I really want to
know :)

Vu