Q: What is IaaS or Private Cloud? And why Enterprise should consider it?
The shortest definition could be. ‘Virtualization on top of an HPC’. Let’s define it like this. What do you think is the biggest limitation to virtualization?
Its, the flexibility of scaling a virtual machine. The scaling will be always limited to the maximum resources available on one particular physical server. So for instanced if let’s say I have a server with 24 Cores and 32GB of Ram. I cannot have a virtual machine which can have more that or even equal to 24Cores and 32GB of RAM.
But let’s say I have 50 such servers. So technically I have 1200 Cores and 1.6TB of RAM. But if for a day even I need a machine with let’s say 50 cores and 64GB of RAM. I can’t have it. I have to buy a new server which has more than 50 cores and 50GB of RAM and then either use it as a physical box or create a virtual machine accordingly on top of it.
But with IaaS, what we do is that we first aggregate our entire datacenter as a single pool of resources and then start provisioning virtual machines on top of it. This is something like first creating a HPC (high performance computing) platform which integrates all our existing resources in one single pool. And then running a virtualization layer on top of it.
Q: What are the other key benefits?
Oh! The benefits are immense. First, the redundancy is inbuilt. So you don’t have to bother about creating failsafe’s, etc. Second. It inherits the functionalities of a Public cloud architecture which makes it elastic in nature. By elastic I mean scaling up and down a virtual machine on-the-fly by adding or removing resources from the cloud pool and that to in an automatic manner and at a need basis. So for instance today a machine needs 15 cores instead of 3. My cloud infrastructure just finds 12 free cores from any server inside my datacenter and allocates it to the VM. And once the need is fulfilled, it releases back the 12 cores to the cloud pool so that they can be used by some other VM.
And third, is the most important benefit is. It gives us the flexibility to add resources from any supporting public cloud if my infrastructure is not able to fulfill a requirement. So, for instance when my VM wanted those 12 extra cores. My Private cloud was only able to find 10 free cores at that time, so it went to Amazon’s EC2 cloud and borrowed the rest of the 2 cores. Used it and when the requirement was fulfilled or 2 more cores were available in my private cloud, it just released the 2 cores back to Amazon. And you will be only charged by Amazon for those 2 cores for that duration of time when you actually used it. This is called a Hybrid Cloud.
Q: Ok, sounds great. So how do we go about it ?
Today there are very few companies who are providing full-fledged cloud architecture to be deployed in-house. One such commercial offering is Enomaly. And one very popular opensource variant which has recently gained a lot of attention is eucalyptus. The reason they have gained a lot of attention because now eucalyptus is available as an out of the box product with Ubuntu Enterprise Server. This means you can now build your own private cloud by using Ubuntu Enterprise Server.
Q: Ok, so what should a CIO watch out for while implementing a Private Cloud?
First, his architecture. As this entre technology runs on the Hypervisor based virtualization, any server which doesn’t have Intel VT or AMD Pacifica, will not be able to join the cloud. So very old servers are already ruledout.
Second is the selection of the Cloud middleware. Right now there is a lot of confusion going on due to lack of understanding. But as a thumb rule, you should select the Cloud platform which is supported by your existing virtualization platform. So for instance if you are a XEN user, then you can select between Ubuntu Enterprise Cloud or enomaly. And if you are a VMWare fan then sticking with VMware cloud would be a better option. For MS Hyper-V users, there is still some time to see the light of hope. Microsoft has said that they will be launching Dynamic Datacenter Toolkit which will let you build your own IaaS based on Hyper-V.
One more thing which is crucial is first accessing whether you will be requiring Hybrid Cloud or not. And if you will, then it also important to see, the cloud platform which you are selecting does support any Public Cloud provider or not. So or instance eucalyptus which is running inside the heart of Ubuntu Enterprise Cloud, is EC2 compliant and can connect with Amazon’s EC2 to form a Hybrid cloud.
Similarly we can speculate that when Microsoft’s Dynamic Datacenter Toolkit will release, that will also integrate well with Microsoft Azure.
