Rackspace announced OnMetal this week at the Gigaom Structure 2014 conference in San Francisco. According to their blog:

“OnMetal offers single-tenant, bare-metal servers that users can spin up or down as quickly as VMs — in a matter of minutes. And there’s more:

• These servers are accessed through an API, just like VMs.
• You pay by the minute, just like with VMs. But OnMetal servers are much simpler and more powerful than VMs.
• They are built on OpenStack software and Open Compute hardware. The API for OnMetal is the OpenStack Nova API. It’s familiar to users of any OpenStack public cloud. And users don’t have to worry about vendor lock-in.
• OnMetal servers are customized for specific workloads.
• There is no hypervisor, and no virtualization tax.
• There is no sharing of metal with any other user.”

The idea behind OnMetal is to allow a user to provision single-tenant, bare-metal servers with the same OpenStack API which is already native to Rackspace. The servers borrow ideas from the Open Compute Project, of which Rackspace is a member. This follows many of the current trends in cloud computing around providing bare-metal options that are cloud delivered.

According to Rackspace, all OnMetal servers use solid-state storage, have no moving parts, and they use only external cooling. Think: Servers you own, and leverage exclusively. However, you can’t go touch them, like you can with traditional hosting and data center services.

But wait a minute. Last week Mirantis and IBM’s SoftLayer division announced their bare-metal-as-a-service cloud plan with Mirantis OpenStack Express. Now Rackspace is following suit with its bare metal offering, which is also powered by OpenStack APIs. So, the world of bare metal clouds, especially OpenStack-powered bare metal clouds, is getting pretty crowded.

The emerging bare metal cloud market provides a way to complement or substitute virtualized cloud services with a dedicated server environment. The best way to explain this is that it’s a cloud service that maps to a dedicated physical server, and you’re the exclusive owner of that service for the time it’s needed.

This eliminates the overhead of virtualization, and allows you direct access to most of the underlying platform services. Thus, bare metal cloud servers do not run a hypervisor, but are delivered using the same on-demand model that most public clouds provide. Examples of bare metal cloud providers include Internap, Liquid Web, and New Servers (also known as BareMetalCloud.com), and now IBM, Mirantis, and Rackspace. Others will come along as well, I’m sure.

Why go bare?

Enterprises leverage bare metal clouds for a few core reasons:

First, there is a need to have more control over the cloud service. Sometimes IT needs to control the platform, and platform services, using direct and native access to the platform. The larger public clouds typically don’t allow this, and thus the bare metal cloud offerings seem to be provided by those cloud providers that are not the top three in the IaaS cloud market.

Second, there are cost issues. In some cases, the use of bare metal clouds is more cost effective than the use of public clouds. This is due to the fact that IT can manage these clouds in such a way that bare metal clouds are more cost efficient than the big public cloud providers because the cloud users have more direct control.

You’ll have to run the numbers to understand if this approach is right for you. Typically this works out when you need to use resources for long periods of time, and when the resources don’t need to auto-scale. Unlike the big public cloud providers, bare metal clouds only provide a finite amount of accessible resources, thus your patterns of use need to consider this characteristic. This is generally speaking. You need to look at what features and functions your bare metal cloud provider offers specifically; they vary greatly.

Finally, bare metal clouds can be the right fit when performance is imperative. Bare metal clouds usually provide better performance because you have direct and unimpeded access to the native platform. There is no hypervisor, and no virtualization tax. This single-tenant approach means that you’re not in competition with other applications or users for the same resources, and your application should be able to run faster and smoother.

The good, the bad, and the bare

There are a few tradeoffs to consider. Most bare metal cloud providers do not have the ability to auto-scale or auto-provision resources on-demand. Public clouds usually allow you to provision as many virtual server instances as you need, and then de-provision them when not needed. They do this by being able to manage the resource instances as virtual machines, and are not bound by physical servers.

The bare metal model is more around dedicated access to physical server resources, much like you would access servers in a traditional data center. Thus, this model is much easier to understand for those who operate and manage traditional systems. Albeit, you can’t go hug your servers anymore.

Of course, you get the advantages of leveraging your own physical machines. This includes performance, as covered above, as well as direct control of storage to deal with issues such as security and compliance. This configuration gets around the objection that many have about the move to public cloud, typically the loss of control and thus the feeling of insecurity that comes with the loss of control. Fundamentally, these are your own machines.

Other advantages include the ability to customize bare metal services for specific workloads. Much like we tune servers for use as database servers, or storage servers in traditional data centers, the same can be done with these as well. Thus, you’ll get even more performance advantages than just the single tenant performance advantages I’ve previously discussed.

The value of bare metal cloud services is in the enterprise’s ability to use cloud to, at times, do certain things with dedicated physical instances. I suspect that most who leverage this technology will also employ traditional cloud servers that are offered using multitenant mechanisms. The option of going single tenant, if needed, on the same cloud platform as OnMetal or other providers, could be the option needed to get the enterprise moving quicker to cloud. If that happens, mission accomplished.