Amazon Web Services announced today the availability of a new service: Amazon EC2 Dedicated Instances. Instead of using a multitenant architecture, the new service gives customers dedicated hardware. In other words, instead of sharing physical servers with other customers, Dedicated EC2 customers will have their own private servers. AWS competitor GoGrid recently announced a similar service called Hosted Private Cloud.
Multitenacy is one of the defining features of the cloud, but it’s also considered risky. The new service takes a lot of uncertainty out of running applications in public infrastructure, but also reduces the elasticity of the service. It’s also more expensive.
Here’s how we explained the trade-offs when GoGrid announced its service:
The advantage over a public cloud is that none of your data is “touching” that of another customer. The disadvantage is that you have to pay for resources that you might not use. The advantage over a private cloud is that you can rent the resources without putting up capital expenditure money or the time and labor of building a data center. The disadvantage is that you still have to trust an outside organization to store your data.
However, according to the announcement from the official Amazon Web Services Blog:
It is important to note that launching a set of instances with dedicated tenancy does not in any way guarantee that they’ll share the same hardware (they might, but you have no control over it). We actually go to some trouble to spread them out across several machines in order to minimize the effects of a hardware failure.
AWS bills for the new service by the hour. There’s a $10 an hour per region fee, plus a cheaper hourly fee per instance. Pricing can be found here.
Here’s an explanation from the AWS Blog of the region fee:
When you launch a Dedicated Instance, we can’t use the remaining “slots” on the hardware to run instances for other AWS users. Therefore, we incur an opportunity cost when you launch a single Dedicated Instance. Put another way, if you run one Dedicated Instance on a machine that can support 10 instances, 9/10ths of the potential revenue from that machine is lost to us.
In order to keep things simple (and to keep you from wasting your time trying to figure out how many instances can run on a single piece of hardware), we add a $10/hour charge whenever you have at least one Dedicated Instance running in a Region. When figured as a per-instance cost, this charge will asymptotically approach $0 (per instance) for customers that run hundreds or thousands of instances in a Region.
This service continues AWS’ shift towards being more enterprise-friendly.
AWS has been adding features and services such as the Virtual Private Cloud Wizard, Cloud Formation and Elastic Beanstalk that make managing applications on the AWS infrastructure easier. It also expanded its support services.
