Testing distributed systems in agile

With more and more people are adopting agile practices; and the focus mostly is on one or two user stories at a time instead of the whole
system, there is a strong possibility that we might oversight some issues with
the infrastructure.

Having said that, it might be very easy to expect the problems and test them. Look at some simple steps that will help you to test such
systems while you are working in agile.

1. Identify all the components of a distributed system. This can be found by looking
   at various documents like architecture etc…, or having a discussion with
   your team members.
2. Think of what can go wrong with each identified component. Be pessimistic about
   their robustness; and write all scenarios. Draw a picture on a boar to
   understand the big picture. It is always good to discuss these scenarios
   with your colleague in the architecture team.
3. Think about how you are going to test each failure. Create one or more test cases
   in your plan for each failure.
4. Ask your business, infrastructure, architecture, developer or any one who can
   answer about what they expect in each scenario and how they are going to tackle the failures?
5. Verify every scenario as early as possible; even
   before starting the development. Note down any differences between the
   expected and actual outcomes. If you
   can’t produce the failure, then try to enforce the failure by asking the
   developer to throw an exception, or take the cable out ;)
6. Now verify if the failure does happen there is a process to tackle the
   failure. This is very important to test the process should there be any
   failure. This might be out of your domain but it is always good to go out
   in the scenarios like this.
7. Don’t hold this knowledge with you; share with your network, service, or help
   desk teams so that they can take actions should there be an issue.

To discuss your particular distributed system or scenario, please do drop me a line and I will be happy to help you.

Shabbir

http://agile-software-testing.blogspot.com/