Five reasons why you'll take your storage to the cloud

And five reasons why you won't...

3. The forever cost

Storage doesn't die; you have to keep paying, forever. 50GB of data on Amazon S3 for a month looks nice and cheap. 50 GB in month 1, 60GB in month 2, 75GB in month 3…that starts to add up and the amount you need to store very rarely goes down.

In addition to the raw cost of storage or computing power you need to pay for bandwidth. Backups are still something you have to do and that is a cost you'll have to cope with, bringing additional bandwidth costs as well as sourcing a second cloud provider to store it on. (What use is backing up to the same cloud provider?)

Cloud computing brings compliance and regulatory burdens. The costs here can get quite high, especially if you use cloud providers outside your own nation. Factor in the opportunity cost of locking yourself into a given cloud provider and that you can't leverage existing investments in hardware, software and so forth.

You might think you're getting rid of the IT department by going cloudy, but you aren't. You're adding layers of things you need to monitor, audit and meet arbitrary bureaucratic standards on whilst replacing periodic one-shot expenditures with a monthly tithe.

Mind you ...

Nothing to something and back again

The cloud is great for bursty workloads, temporary workloads, or dev environments. It's great for getting something working fast or for a fixed timeframe. Want to run for president? Well, you could invest in a sea can full of servers to do the work you need, or you can spin it all up on a public cloud for a couple of years and then tear it down after the election's over.

Pay as you go means no upfront investment. If your business succeeds then it will pay the bill at the end of the month. If it fails, it fails. You don't have to dig in your jeans to buy a great big pile of infrastructure just to play the game. All you need is the first month's "rent".

4. If it ain't broke, don't fix it

The emergence of a new technology does not mean the eradication of so-called legacy technologies. You may already have a great non-cloud solution to a business need. Switching to the cloud means retraining your staff, changing significant internal business processes and will likely cause many unforeseen disruptions.

New technologies should augment rather than supplant old technologies. We use what works – and what we're comfortable with – until there is a demonstrable reason to replace it. In many cases we never replace the old technology entirely, keeping the older stuff around in case of emergency.

If centralized, utility-style X were always better than roll-your-own, why do hospitals and datacenters have backup generators? Shouldn't the national grid be "better"? If what you have works then there just isn't a need to jump to the cloud. Even if you do make the leap, you'll probably want a backup local IT plant for some time to come.

Sure about that?

Change as a service

As much as existing technologies and business practices are a nice security blanket, not everyone wants to keep things as they are. Sometimes a swift kick in the butt is what's required and this is something that cloud services seem regularly able to deliver.

Everybody loves the idea of doing without the IT department – or at least giving them a good scare to keep them in their place – and cloud computing can be used to that effect. It can also be used to provide "simplicity as a service": when an incumbent software provider has become hopelessly complex and difficult to use you can bet a cloud provider will pop up to replace them with something far easier to work with.

5. Data ownership

Do you have access to your data in the cloud? Not the data as presented you through the interface of the software, but the raw data needed to pick up and move to another vendor. There are business continuity questions to be asked here.

If you license a product, you can run it in your data center for a decade, or transfer data out of it at any time. You own it. ''How do you get your data out of the cloud? Can you transfer it to a different cloudy service if you need to? What if your provider goes out of business or gets sued into oblivion? If your cloudy provider simply isn't there tomorrow, how to you access and use that data? Backups don't matter if you have nothing to restore them to!

What about more temporary outages? If the cloud service goes down, will there still be useful work for staff to during the day? How long can you go without your cloud service provider? How long would it take you to restore/convert your data from your existing cloud provider into something usable enough to keep the business running? Would your business even survive an outage of that length?

Mountain out of a molehill?

Cloudy similarity

Many kinds of data are straightforward and generic. Email, file storage, and some kinds of big data you've designed the analysis or reports for. If an IIS website/SQL server dies on Microsoft's Azure cloud, it's not a big deal to arrange a replacement.

Some cloud providers have easy transfer mechanisms to other apps, e.g. Quickbooks online to the Quickbooks desktop client. For others there are cloud brokers who can take the task of data migration off your hands ("oh shit" as a service.)

Similarity at this level makes the cloud a natural extension of your datacenter. IaaS offerings are not something you generally have to worry overmuch about. Do your backups right and you can light up replacements anywhere. PaaS is something you can probably build a backup cluster for and SaaS providers are slowly starting to come around to the realisation that people don't appreciate lock-in.

Like it or not, the cloud is here to stay. There are reasons to use it and reasons not to. There are reasons to use only some aspects of it and reasons to go whole hog. As always, please leave your ideas in the comments below. ®