[NTLUG:Discuss] NAS devices

[Joe Torma]

Subject: Re: [NTLUG:Discuss] NAS devices

Ralph wrote:
> Howdy,
>   I get to spec out and probably buy a NAS for the office.  I see some 2
> U servers that have 8 exposed 2.5 inch drive bays.  When I think of 2.5
> inch hard drives, I don't think of drives that can take heavy use.  Are
> these new drives built better than laptop drives?  Is SAS better than
> SATA?  SAS drives seem to go up to 146 GIG and SATA up to 500 GIG.  At
> least, that is what Pogo Linux says.  I don't need huge amounts of
> throughput.  But, reliability is very important.  Any comments?

SAS is touted as more reliable and more "enterprise class".  There is a
major convergence happening now around all of that technology.  You should
be able to find 300GB and 400GB SAS drives, and SATA capacities run to 1TB.
Spindle speeds of the SAS drives tend to be higher than their SATA
counterparts, but MTBF figures are pretty comparable except at the low end
of the SATA chain, over which SAS has a clear advantage.  If reliability but
not throughput is your aim SATA should be fine.  If you need every bit of IO
you can get, spend the $$$ on SAS IMHO.  Major corporations are deploying
massive SATA arrays daily.  They work, particularly if you set up your array
for maximum redundancy and throughput - RAID 10 over many drives is a good
example.  RAID 6 would be my next choice.

2.5" drives have definitely been industrialized lately.  Personally I like
the bigger ones, but I am a dinosaur like that...  2.5" definitely
represents the future of enterprise storage (until solid state storage
becomes more affordable in massive quantities) as density is higher and
power consumption and heat are lower.  That said there are some 2u chassis
which expose 8 3.5" drive bays if you want to build your own...  

Given the opportunity to pick NAS (including NDAS) or SAN, though - I would
pick a SAN every time, as has been discussed here recently. 
 
_______________________________________________
http://www.ntlug.org/mailman/listinfo/discuss