[TriLUG] Setting Up RAID-5

[Brian Henning]

Hi Gang,
   Just looking for some advice on setting up a RAID-5 file server at 
home.  I'm imagining putting six 160GB 7200rpm SATA-II drives in a 
machine with two simple Promise TX4 four-port controllers and doing all 
RAID functionality in software (since 6+ port RAID-5 capable cards are 
way more expensive than two dumber cards).  My questions:

  - Is RAID-5 in software a bad idea?  I hear it's a little 
computationally intense on write as it has to recalculate parity blocks 
for each stripe that is written.  How much computer horsepower do I need 
to not have the bottleneck be processor clicks?

  - Would it really be a better idea to sink the money into a RAID-5 
capable controller instead?  My fear is that if the controller dies, I 
hear you have to be able to replace it with the exact same controller if 
you want your data back.

  - Assuming software RAID, does lotsa RAM help any?

I'll probably be using CentOS as the host OS, so that keeps it on topic. ;-)

For the curious, the purpose of this will be a central file server for a 
home music studio.  A place to store the GB upon GB of samples that come 
with quality sampling soft-synths (just bought dfh Superior.. 35GB of 
samples!), as well as finished projects (active projects would be on the 
DAW machine, to reduce disk latency).

Cheers,
~Brian

-- 
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Brian A. Henning
strutmasters.com
336.597.2397x238
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