Throughout the history of IT, we’ve had our share of purists. OS purists, language purists, etc. The stark one was the “That is not Object Oriented Programming” crowd. While the poster-children of IT purity, we don’t really hear from them anymore—and thank goodness for that.
But a new crowd has reared its head in DevOps specifically, development more generally. They don’t believe there is ever a reason to modify a running container. Call them deployment purists, though maybe one of you has a better term.
Like OO purists, this approach ignores the reality of the environment we work in. Yes, the best option most of the time is to fix an issue and roll out a replacement container. But, the fact is that claiming anything else is not using containers “correctly” is patently wrong. My go-to example for why I say this is the easy one, because explaining complex infrastructures while trying to make your point is a waste of time.
Rolling feature releases in most organizations that do them regularly are achieved with environment variables on feature tags. But changing an environment variable is changing an instance. So, are all these organizations wrong, or perhaps the idea of purity is the problem when it comes to IT? Certainly, the driver for DevOps in many organizations was that purity had created islands of toolsets with varying delivery timelines and quality controls.
I contend it is past time to let purity be a guideline instead of a mantra. Yes, in most situations rolling out a new instance is the correct response, but in many–live applications that will drop connections and lack enough redundancy to bleed users off, for example–the correct solution is to modify the instance. “Never change production” is a good mantra, but it is a terrible purity test. We should avoid it, while acknowledging that not all situations allow us to make that choice.
Keep on rocking it. We’re weeks into COVID, and I can hear the stress in my operations friends’ voices. Know that the rest of us are grateful to have you keeping things running for us and bending over backward to make certain we have the access we need. Thank you, from me, for all of the people relying upon you.
— Don Macvittie
