Are Rackspace's Cloud Servers really cloud hosting?

Mnn, you're not really confusing things, or at least you're not more confused than many other people are about "cloud computing". Cloud computing (CC) has become one of those trend-words, fashionable words that get used in lots of different circumstances.

To me, cloud computing just implies a service somewhere between Infrastructure as a Service and Platform as a Service. (Themselves also 2 very abused words with many different interpretations.)

For me, auto-scaling with demand is not a required part of cloud computing. If you look at it, neither Amazon AWS nor Windows Azure had auto-scaling as part of their initial offering. Only Google AppEngine had this, and initially at the expense of other severe limitations on the run-time environment.

Clearly auto-scaling is desirable, and AWS has had it for some time through Rightscale and other 3rd party providers. But it's not the only differentiator between plain VPS and Cloud Computing.

Some of the key differentiators between VPS and Cloud Computing for me are:

• Management interface that is optimized for a fleet of VPS's and not just 1-5 VPS's.
• Presence of load balancing services and similar network-level services.
• A business model that prices storage, compute and bandwith differently, and allows a great deal of flexibility in the consumption of these.
• Sheer size. To me, if you can provision 10-100 virtual machines with short warning, then you're a VPS provider. If you can provision 100 - 10.000 VPS servers with short warning, then you're a cloud computing provider.

I just wanted to throw this out there, as in my other answer to a Cloud hosting question:

"Cloud hosting" is just a re-branded VPS, most cloud solutions scale in no way. You could argue this on several points, but this is what it boils down to.

The one thing that I have seen more and more "Cloud" providers offer is instant provisioning of servers - this is a differentiator to the old style VPS that had to be manually provisioned.

I, like you, was very confused about cloud hosting until I came to this conclusion. In my own definition of cloud hosting auto-scaling was a necessary component, however most providers do not offer this (besides being able to deploy a VPS as well). "Cloud" seems to be a marketing term more than anything else.

Hope that helps clear things up for you.

I have been hosting with the RackSpaceCloud (Mosso) for about 18 months, and the best way I would describe the service is "cloud-like".

The system DOES scale up automatically when your traffic spikes. We got an indirect mention in a major Hollywood movie, and our traffic more than tripled when the movie was released.

All we saw was our "compute cycles" go up (this is a measurement of how many server's worth of resources you are using to run your site).

However, not all is as rosy as it may sound.

While the first 12 months of hosting went pretty smoothly, RackSpaceCloud has become completely unreliable for the past 2-3 months.

I believe that they must be pushing past the limits of their immature "cloud" system.

Our site was down for more than 200 hours last month. Yes, that is an "up-time" percentage of less than 50%. The reasons provided have ranged from connectivity issues, security issues, failing hardware, scheduled and unscheduled maintenance blackouts and "misbehaving nodes" and my favorite: "we don't know what is going on".

In my opinion, they have a couple of years to go before their system is mature enough to handle real "cloud" computing requirements.