[ale] [OT] Home nas

[JD]

Backups don't need RAID. You want RAID on the main storage, if that is a
requirement.

For simple backups, buy a USB3 dock and connect it to a router with USB ports
for storage.  Using a dock means he has "unlimited storage", just swap in a new
2TB hdd when the old one fills up.  If performance isn't good enough, newer
routers should support USB3 soon.  Even some of those $50 media streaming
devices will share USB HDD storage on the network.  I'm positive that a WD-TV
Live HD does.  At 100base-tx, it is painfully slow compared to everything else
that is GigE connected here.

USB3 is not a good idea for anything other than backups or streaming media,
IMHO. There has been a queuing issue with USB for years. It handles 1 or 2
different requests at a time nicely, but not 5-20 like a full OS will make.
There are eSATA docks for that, but then he needs to leave a PC on all the time.
eSATA behaves just like internal disks. Same performance, same command set.

I wouldn't completely knock out building a NAS-PC either.  The AMD APUs and Atom
APUs can use 20W of power + however many HDDs are inside.  Last month if saw
(and purchased) a Slickdeal E-350 MB+APU+case for $100. That's hard to beat on
the price.  Drop in 1-2G of old RAM and an old HDD means a new system is ready
and will be stingy on electricity.  I am not using it as a NAS, but might in the
future.

I have a home-built NAS with an external 4 disk array currently. That is primary
storage running Linux software RAID.  To back it up, a USB3 WD external disk is
used. Simple, cheap and effective.  If the backup disk fails - oh well.  That
same disk array has been moved between systems and Linux installs multiple
times. It was a non-event every time, extremely flexible.  Software RAID can be
slower than HW-RAID.  The RAID5 here is much less speed than a single WD Black
drive for writes. The OS disk cache is about 4G on that box, so the first 4G of
transfer is always 65-75MB/s. Writing large files (10-22G HD recordings) to the
single Black drive achieves about 40MB/s over the network, after the cache is
full.  Going to the RAID5 storage might get 10MB/s after the cache is full.
Same client, same server, same network, just the storage being written onto is
different. Guess which drive I transfer new files onto over the network?  To be
fair, the Black drives are fairly new and the disks in the array are 5.5+ yrs
old.  I'm burning in replacement HDDs as I write this.

With purchased NAS devices, much flexibility is gone. There are limits set by
the maker. I guess that is what you are asking - about those limitations?

Anyway, I hope these ideas are helpful to finding the best answer for his needs.


On 09/16/2012 12:56 PM, John Anderson wrote:
> I guess the issues other than the basic one of price would be:
> reliablility.
> 
> raid 1
> 
> Ability to pop a drive out and read it if the unit fries. Are there 
> systems with software versus hardware raid? My understanding is that 
> software is easier to recover if the hardware fails.
> 
> Transfer speed is probably not an issue. This is more for the first 
> layer of backup for multiple pc's in the household. It probably won't be 
> getting hammered on a regular basis.
> 
> On 09/16/2012 12:39 PM, JD wrote:
>> On 09/16/2012 12:02 PM, John Anderson wrote:
>>> Any recommendations/cautions about picking up a home nas? It's for my
>>> brother in law so he probably won't want a re-purposed PC. Looking to
>>> spend <$500
>> You usually get what you pay for.
>> http://www.smallnetbuilder.com/nas/nas-charts/view will get you (or him) started.
>>
>> There are many other caveats, but without requirements or use scenarios, I can't
>> begin to make any suggestions.
>>
>> If he wants low price over all else, there are cheap 1 or 2 disk options without
>> any advanced capabilities. However, these have pretty poor performance, but that
>> may not be an issue.
>>