Many DBAs and operational staff regularly stress over software deployments to production systems. Even when the administrator has built and tested the deployment scripts, there is still a nagging fear that something will be missed, incurring downtime for systems. I think automation, building an ALM And DLM process, as well practicing deployments in other environments is the way to alleviate concerns, but that’s a discussion for another day.
However, I had a question this week that is related to the deployment process. I’m curious, do you smoke test your production deployments?
Perhaps the first question is do you know what a smoke test is? If you don’t, maybe you want to read a bit about smoke tests. If you know about smoke tests, do you have anything more than testing if a server or service is running?
If you don’t, that’s fine. In fact, throughout most of my career our smoke tests consisted of checking that we could connect to a server or database. In fact, in most cases, we did this manually. We’d deploy some change or patch, then see if we could connect to the server. Sometimes a person would connect with an application, but not much more than logging in. Since many apps were fairly simple client-server applications, this was usually sufficient, but there were times we had problems with not all changes being deployed. A few times we didn’t realize this for days.
If you deploy changes, there should be some small things that you check as an method of validating that your systems are working correctly. There may be initial checks that machines are actually running. If those checks fail, there’s no point in going further. However, if the basic connections work, perhaps you should have a few critical functions that can be called and ensure that basic functionality of the application is there. Or that your new changes actually are deployed. If you have complex, interconnected systems, maybe you want a few smoke tests that you can automate and quickly ensure everything is running as expected and communicating.