Minimizing the impact of code changes on multi-tenant applications requires a little devops “magic” and a broader architectural strategy

Ignoring the unavoidable “cloud outage” hysteria that accompanies any Web 2.0 application outage today, there’s been some very interesting analysis of how WordPress – and other multi-tenant Web 2.0 applications – can avoid a similar mistake. One such suggestion is the use of a “feathered release schedule”, which is really just a controlled roll-out of a new codebase as a means to minimize the impact of an error. We’d call this “fault isolation” in data center architecture 101. It turns out that such an architectural strategy is fairly easy to achieve, if you have the right components and the right perspective. But before we dive into how to implement such an architecture we need to understand what caused the outage.