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Internal Costs Per Gigabyte — What Do You Pay?
CodePwned writes "I recently took over a position at a rather large company where I discovered my group was paying $30 per gigabyte per month! That's $360 per year per gigabyte to our own IT department. While I understand costs are different depending on the scale, redundancy, backup and support methods, there doesn't seem to be any good papers on what range you should expect your costs to be. So far, my research shows an average of $1 per gigabyte or less for internally hosted space. What do you pay?"
Bandwidth? Storage? Backup? Downloads from a particular site? What the hell are we talking about here?
I suppose it all depends on what, and how, you're measuring. Is that money spent on backup tapes, raid systems, flash drives, or what? Is that for offline storage, frame-relay throughput, ISP bandwidth. Does IP telephony get rolled up in that? The question seems a little vague to me.
When our name is on the back of your car, we're behind you all the way!
You've not allowed for power, network, or backup in your costing. Try again.
What you may be seeing, especially if you are working for a very large company, could just be a cost allocation scheme, not a real money cost as you are thinking of it. If your department brings in revenue, the organization needs to match expenses to it for purposes of Management Accounting.
For instance, imagine you know it costs $X to run one of your cost centers. That dollar amount includes everything from the manpower, the equipment, the facility...everything. Now, they need to assign these costs to the departments that actually make money in a way that makes sense. They could do this by carefully costing out each service they provide and assigning an overhead rate, blah blah. That tends to be a pain. You do it if you have to...but you try not to have to. Another, easier, way of doing it is determining a usage metric (CPU hours, GB of storage, number of tickets) and using that to determine each profit center's percentage allocation of the overall cost.
So, the $60 per GB may not even be close to a market rate for storage. However, if all the departments used twice as much storage next year, the per GB cost might fall to $31 per GB (slightly more than half to account for the fact that there would obviously be more real costs). Conversely, if you convinced your management to contract externally for storage, everyone else might find their per GB cost rise, since the fixed costs would be static.
Also doesn't allocate anything for the cost of the person doing the maintenance/monitoring - that person doesn't come for free usually.
At those costs, one terabyte of data stored for three years would cost roughly $1.1 million. I find it hard to believe that you could legitimately build a SAN that stored 1 TB for that amount of money and not have hit some sort of performance wall that made the expense superfluous. I mean, at some point, you're maxing out multiple 10GigE fibre channels from your SAN and thinking "How can I spend the rest of this money?"
Having done the modeling for this, here's some components to consider.
I have one example (AUD) where this works out as follows:
Do the maths above: excluding power, staff, tape libraries and rack space etc, it's already over $25 per usable GB for Tier 1 (and $13.57 in this model for the Tier 3 storage). Redundancy is baked in. Spare disks in the SAN are baked in (so a disk failure means immediate rebuild not "wait 4h until a replacement can be installed by an engineer" rebuild. And for this cost, we also have things like automatic deduplication of data (backup and online), data replication, historical backup to tape and so on and so forth.