RAID autodetect?

[Bill McGonigle]

On Nov 25, 2005, at 06:59, hewitt_tech wrote:

>  you might have quite a difficult time getting the configuration 
> correct so that you could recover your system. I thought that hardware 
> RAID arrays (usually SCSI) didn't have this problem since the platform 
> software only sees a disk or disks and not the underlying RAID 
> hardware.

Autodetect should help with that because you don't need the .conf files 
- a copy of the RAID configuration is stored in some sort of RAID 
header, which makes recovery easier.  The Fedora recovery CD, for 
instance, will detect and understand them.

Hardware RAID is certainly easier to configure and you can do things 
like fiberchannel arrays which support things Linux doesn't (fiber 
channel networking, IDE hotswap, for instance).  But... they're 
typically slower (the hardware geeks on the PostgreSQL list claim 5x 
performance for a Linux RAID mirror over an Adaptec SCSI RAID 
controller) and if you have a unique RAID board burn out you're totally 
screwed until you can purchase a new, identical, one (onsite spares 
required for critical apps) .   With Linux RAID your RAID pack is 
compatible with any generic PC.

-Bill
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