Cloud Foundry zero downtime deployments
Software releases can be a very painful experience and typically involve some downtime, especially to traditional monolithic applications. As we have seen in previous posts the process of pushing code to a platform like Cloud Foundry is quite easy but it still a push can take between one and two minutes and during the most part the app has to be down. One or two minutes doesn't sound too bad for most people, but while working for EMC I have met some customers for which "mission critical" has a complete different meaning. I have seen systems where 1 second downtime could be measured in hundreds of millions of dollars. There is lots of talk about CI/CD (Continuous Integration and Continuous Delivery) but here we are talking about accepting a minute downtime. Well, the good news is that Cloud Foundry has the tools to allow you to do a zero downtime deployment. The most common procedure is typically referred to as "Blue-Green deployment. The trick is to have two...