[K12OSN] Knowledge turned crisis

[Les Mikesell]

> From: Liam Marshall
> 
> anything wrong with 4 - 80 GB 7200rpm EIDE drives with 8Mb 
> cache running on a raid controller(as yet to be determined) 
> in a configuration like 1 
> + 0 or 0 + 1?  This gets me effectively 80GB capacity and redundancy
> with the ability to withstand 2 drives dying, right?

With most cheap IDE controllers you are better off running Linux software
raid than the controller version which is mostly software anyway.  You
really want to keep each drive on it's own controller so you'll need
some kind of extra card to handle 4 drives. Note that you can't lose
any two drives at once - you are only covered if you lose one of the
drives with a still-working mirror. 

> this would get me, correct me if I am wrong, both redundancy and some 
> performance increase, yes?

Doing raid0 may give a performance increase, raid1 gives redundancy.  You
can do either or both.  Doing 2 separate raid1 mirrors would mean that you
could recover the data from any single drive if you plug it into another
machine.  That is difficult or impossible with other raid schemes but if you
have some other backup may not matter to you.

---
  Les Mikesell
    les at futuresource.com