As we move from “tens” to “hundreds” to “thousands” of nodes in a typical data centre we need new tools and practices. This hyperscale story – of hyper-dense racks with wimpy nodes – is the big shift in the physical world which matches the equally big shift to cloud computing in the virtualised world. Ubuntu’s popularity in the cloud comes in part from being leaner, faster, more agile. And MAAS – Metal as a Service – is bringing that agility back to the physical world for hyperscale deployments.
Servers used to aspire to being expensive. Powerful. Big. We gave them names like “Hercules” or “Atlas”. The bigger your business, or the bigger your data problem, the bigger the servers you bought. It was all about being beefy – with brands designed to impress, like POWER and Itanium.
Things are changing.
Today, server capacity can be bought as a commodity, based on the total cost of compute: the cost per teraflop, factoring in space, time, electricity. We can get more power by adding more nodes to our clusters, rather than buying beefier nodes. We can increase reliability by doubling up, so services keep running when individual nodes fail. Much as RAID changed the storage game, this scale-out philosophy, pioneered by Google, is changing the server landscape.
In this hyperscale era, each individual node is cheap, wimpy and, by historical standards for critical computing, unreliable. But together, they’re unstoppable. The horsepower now resides in the cluster, not the node. Likewise, the reliability of the infrastructure now depends on redundancy, rather than heroic performances from specific machines. There is, as they say, safety in numbers.
We don’t even give hyperscale nodes proper names any more – ask “node-0025904ce794”. Of course, you can still go big with the cluster name. I’m considering “Mark’s Magnificent Mountain of Metal” – significantly more impressive than “Mark’s Noisy Collection of Fans in the Garage”, which is what Claire will probably call it. And that’s not the knicker-throwing kind of fan, either.
The catch to this massive multiplication in node density, however, is in the cost of provisioning. Hyperscale won’t work economically if every server has to be provisioned, configured and managed as if it were a Hercules or an Atlas. To reap the benefits, we need leaner provisioning processes. We need deployment tools to match the scale of the new physical reality.
That’s where Metal as a Service (MAAS) comes in. MAAS makes it easy to set up the hardware on which to deploy any service that needs to scale up and down dynamically – a cloud being just one example. It lets you provision your servers dynamically, just like cloud instances – only in this case, they’re whole physical nodes. “Add another node to the Hadoop cluster, and make sure it has at least 16GB RAM” is as easy as asking for it.
With a simple web interface, you can add, commission, update and recycle your servers at will. As your needs change, you can respond rapidly, by adding new nodes and dynamically re-deploying them between services. When the time comes, nodes can be retired for use outside the MAAS.
As we enter an era in which ATOM is as important in the data centre as XEON, an operating system like Ubuntu makes even more sense. Its freedom from licensing restrictions, together with the labour saving power of tools like MAAS, make it cost-effective, finally, to deploy and manage hundreds of nodes at a time
Here’s another way to look at it: Ubuntu is bringing cloud semantics to the bare metal world. What a great foundation for your IAAS.