Linux Hardware RAID Configuration

[Kevin Brown]

>> I'll be happy to help a lot more once I'm back in town.  (Tuesday
>> will probably be the soonest).
> 
> Well looks like I might be bailing on this plan after your comment
> below.
> 
>> What I ended up doing  was: three sata drives, two mirrored, one 
>> hotspare.  I created two slices on each disk, done for the root
>> slice, and one for the LVM slice.  Then build the soft raid config.
>> Then used LVM to further divide up the 2nd slide into my various
>> file systems.
> 
> Oh, for pete sake...that's an awful pain...and at least one more
> drive than I was planning to use.

You don't need 3 drives to do mirroring.  He used 3 so that if one 
failed the system would already have a spare to put into place without 
the user having to do anything.  This is good since you might not be 
able to check the status of the drive every day or get a replacement 
quickly when one does eventually fail.

>> It was a pain in the butt, and I'll never do soft raid again - but,
>> a 3ware card was $2-300 over the budget at this time.  Next time I
>> budget a bit more.
> 
> Ok, well I'm now thinking of bailing on the whole idea.  I'm already
> way over my 'fun' limit already. It was really only a nice to have
> thing on this system anyway -- just looking for that extra level of
> assurance since drives have gotten so reasonable -- and it was
> supposedly on the mobo.

Welcome to the reality of system reliability.  You think this is a pain, 
try developing a system that will give 99.999% uptime. That is only 
around 5 minutes of downtime in an entire YEAR.  One, maybe two reboots 
of most systems would come very close to that not counting the time that 
might be needed to reliably shutdown and start up various services and 
applications.  This is where failover and multiple levels of system 
level redundancy come into play (e.g. dual power supplies, UPS, failover 
NIC connections, failover hardware (heartbeat software) or round 
robin/load balancing systems).

>> Also, I ended up running ubuntu on this thing.  Advice: make sure
>> you run a 2.6 kernel, the 2.4s blew up (deb + ubuntu).  Also, the
>> 64bit deb port is 1/2 baked at this time.
>> 
>> You could always try Solaris x86 :)
> 
> Not a bad idea -- if I abandon my RAID plan I've got a another whole
>  drive ;-)