Thoughts of virtualization – Part II
I really like going to events at the GarageGeeks (www.garagegeeks.org) – apart from meeting with some friends, having a good laugh and enjoying the casual beer, the technical talks and the general subjects that are being attended at a gathering are always interesting.
This time, the Geeks had decided to focus on Cloud Computing, trying to introduce the somewhat highly evolving field of the IT/Computing industry to the visitors of Garage. Now, I have to admit that during the past few weeks I’ve been studying the various aspects of utilizing Amazon EC2 services, and I’ve come to the somewhat problematic conclusion: “Cloud computing is a wonderful solution, as long as you have clear and concise control over your computing cloud!”
The main problem with traditional cloud computing, as offered by Amazon and others, is that the physical boundaries of your system are somewhat unknown – not to you and in some cases, not to your provider either. Let us imagine a Tier based architecture platform, implemented utilizing Amazon EC2 technologies – our web front-end may be located in the US, the application server in the UK and the Database in Zimbabwe for all that matters – in accordance to EC2 and traditional cloud computing, that is fairly normal.While EC2 and some other providers had introduced the idea of a Zone, making sure that your virtual servers are all located in the same physical data center, other solutions are yet to follow.
The above design introduces an interesting “Critical Path” management problem, tied deep into the Tier based architecture design pattern. Companies such as GigaSpaces and others had made it their business to cash in on the problem, by providing a distributed, memory based, middle-ware – literally sweeping the “Critical Path” problem under the rug. However, as the platform will evolve, “Critical Path” issues have a tendency to re-appear, usually, a lot more serious than the original problem – due to new constraints and new operational paradigms within the operational construct of the cloud platform.
So, question be asked: “Is cloud computing good? Can you really build a full service based upon cloud computing services?” – The answer isn’t a straight forward yes or no. For example, while I have a couple of servers on EC2, serving me as development servers mainly, I’ve built my own little cloud environment on my own servers – used for production usage. I’ve used a mixture of OpenVZ servers tied together with my own provisional interface to create a seamless cloud, enabling me to replicate servers, control their operational structures at east and most important – expand my cloud rapidly by introducing new servers to my cloud.
Is my paradigm good for all purposes? I can’t really say – it works for me, it may not work for you. The thing is this, don’t expect cloud computing to come in and solve all your problems, you may run into new ones you are completely unfamiliar with.