Nate Vack wrote:
> On Thu, Aug 27, 2009 at 1:57 PM, Ryan Ordway<[log in to unmask]> wrote:
>
>   
>> $213,360 over 3 years
>>     
>
>   
>> If you're ONLY looking at storage costs, SATA drives in enterprise RAID
>> systems range from about $1.00/GB to about $1.25/GB for online storage.
>>     
>
> Yeah -- but if you're looking only at storage costs, you'll have an
> inaccurate estimate of your costs. You've got power, cooling, sysadmin
> time, and replacements for failed disks. If you want an
> apples-to-apples comparison, you'll want an offsite mirror, as well.
>
> I'm not saying S3 is always cost-effective -- but in our experience,
> the costs of the disks themselves is dwarfed by the costs of the
> related infrastructure.
>
>   
I agree that the cost of storage is only one factor. I have to wonder 
though, how much more staff time do you need for local storage than 
cloud storage? I don't know the answer but I'm not sure it is much more 
than setting up S3 storage, especially if you have a good partnership 
with your storage vendor. With cloud storage you still need other 
backups and mirrors, so I don't see the off-site mirror as an argument 
in favor of the cloud. You should have that redundancy either way.

Yes, maybe you save on staff time patching software on your storage 
array, but that is not a significant amount of time - esp. since you are 
still going to have some local storage, and there isn't much difference 
in staff time in doing 2 TB vs. 20 TB.

You may some time on the initial configuration, but you still need to 
configure cloud storage. Is cloud storage that much easier/less time 
consuming to configure than an iSCSI device? Replacement for disks would 
be covered under your warranty or support contract (at least I would 
hope you would have one).

The power and cooling can be a savings, but in many cases the library or 
individual departments don't pay for electricity, so while *someone* 
pays the cost, it might not be the individual department. Cooling and 
electricity costs are an actually a great argument for tape for 
large-scale storage. Tape might seem old fashioned, but in many 
applications it by far offers the best value of long term storage per GB.

Again, I'm not totally against the cloud and there are some things I 
think it could be very useful for, but the cloud doesn't make up for the 
lack of (or just bad) planning. As someone else said during this thread 
this is really more of a management issue than it is a technology issue. 
Yes, technology is involved in the solution, but proper planning and 
long term commitment is more important than the technology du jour. 
There are many different options from cloud to tape to disk, but no 
matter what you choose without a long term digital preservation plan, 
you might be doing storage but you are not doing preservation.

Edward



> Cheers,
> -Nate
> Waisman Lab for Brain Imaging, UW-Madison
>