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Posts tagged ‘cloud computing’

Jul 6

It’s human to error, but real catastrophes require computers

A typical server "rack", commonly se...

Image via Wikipedia

InfoWorld published a story last week titled the Top 10 worst cloud outages. The article certainly makes for good reading, although it would be nice, if people would stop acting so surprised about cloud failures. It is after all just software and server hardware, and, while very clever, all technology fail at some point despite the recent hype. In fact, the more you have, the more likely it is to experience failures. A Cloud vendor would actually need to work harder to just match a ‘simpler’, traditional data centre in terms of high availability.

The Butterfly Effect

The most important lesson taught at a first aid course is to ‘stop the accident’ – the same is starting to apply to highly interconnected software systems.

The recent Gmail failure caused by a software bug discovered during the deployment process, yet it still managed to affect 0.02 percentage of Gmail users. Skype has experienced two outages due to a combination of localised high load and a (replicated) software bug (discussed here and here). Amazon’s recent failure was a network misconfiguration which escalated into a data replication storm.

High availability built through infrastructure replication typically still share the same software infrastructure, e.g., multiple deployments, same code, so a bug in one equals a bug in all. The space shuttle had two separate flight systems to avoid this and achieve high reliability – not the same as high availability – which in a cloud computing context equals the ability to use two (or more) alternative cloud vendors for the same service.

The case of ‘localised failure bringing down an entire network’ isn’t new of course. Read more

May 21

Architecture Reviews, Technical Debt, and the Cloud

The architecture review process is (or at least should be) a critical part of any IT project – especially considering the seemingly ever increasing level of complexity most IT architects face. It is a key opportunity for stakeholders to ask the ‘why this’ or ‘how about that’ questions with the dual goal of increasing their understanding as well as checking whether the architect is on the ball. It is a game of hunting down all of the critical assumptions – get them wrong and your project will be well on its way to failure.

Any architecture is built on a set of assumptions. We don’t know everything, and we need ways to limit our scope, so we use assumptions to reduce the unknowns and control our commitments. But in the process of making assumptions, we may incur ‘technical debt’. Read more

Apr 18

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Time to get our heads out of the cloud

Wilhelm Röntgen discovered x-rays in 1895 which resulted in a worldwide flurry of excited investigations, speculations and wild claims. The American Institute for Electrical Engineers wrote a couple of years later that “the whole world seems to have been working on it for all this time without having discovered a great deal with respect to it“. At the moment, that sounds a bit like Cloud Computing. We all know about the potential infrastructure flexibility, cost savings, and elastic performance scaling, but the big question remain – how do enterprises with decades of IT infrastructure take advantage of Cloud Computing?

Bernard Golden recently wrote an article about ‘taking an application to the cloud’ versus ‘taking the cloud to the application’ – another way of saying that unless you design your application for the cloud, the application will remain hostage of old style infrastructure constraints. There is little point in elastic infrastructure if the application cannot be ‘stretched’.

Read more

Feb 18

Oracle’s Architect Day on Cloud Computing – a contradiction?

TechForum - Technology Forecast: Cloudy for 2010

Image by BasicGov via Flickr

Given comments by the Oracle’s CEO, Larry Ellison “Maybe I’m an idiot, but I have no idea what anyone is talking about. What is it? It’s complete gibberish. It’s insane. When is this idiocy going to stop?” and the recent closure of Sun’s Cloud, I figured this one should make for an interesting day. So I went along to the Grace Hotel, Sydney.

And I’m glad I did – the organised presentations and panel discussion demonstrated, that Oracle and Cloud are by no means a contradiction – in fact, it was nice to see and hear (at least) one vendor preaching some calm among the hype. And yes, the food was nice too.

According to Gartner’s Hype Cycle (as quoted by Oracle), Cloud Computing is at the Peak of Inflated Expectations, and we are about to decent into the Trough of Disillusionment. But rather than writing off Cloud Computing altogether, there are a number of potential benefits to emerge on the Slope of Enlightenment.

Better and Flexible Pricing Models for IT

Enablement of IT departments to implement effective ‘charge back’ model for IT services. The difficulties to charge for technology services as per usage than per server have in my experience been a major show stopper for effective sharing of infrastructure – resulting in later expensive, but inevitable, consolidation projects. Avoiding them in the first place would be a far more cost-effective approach and a lot less risky.

Better Enterprise Architecture

Questions like security, privacy, vendor lock-in and what do we put in a public cloud are major concerns. But regardless of the applied technologies, it all starts and ends with effective governance. And effective governance doesn’t happen without a good approach to Enterprise Architecture. The Enterprise Architecture challenge is not just about effective and better implementations of current best practice, it is also the enhancements of the frameworks to cope effectively with cross-company collaborations (as noted by Philip Boxer in his blog, Asymmetric Design).

Cheaper Infrastructure – Upfront and Total

Tim Rubin, (Senior Enterprise Architect, Oracle) described the concept of ‘cloud bursting’ – e.g., where companies purchase additional capacity for the (few) times a year it’s needed. This would enable companies to size their own infrastructure (maybe as a private cloud) for the typical performance and load requirements (lower upfront) and ‘rent’ infrastructure for the peaks. Neither public nor private clouds are able to offer both, but the private cloud combined with the ability to burst into public clouds offers this opportunity.