Getting started with blue-green deployment
Teams tend to reach for this after something has already gone wrong. A short on-ramp to blue-green deployment for teams who have not touched it before.
The bill is a design document: it tells you exactly what your architecture actually does. The teams that stay on top of it are the ones who put it on a calendar rather than a wish list.
Why it matters
Running two environments makes rollback instant. That sounds obvious written down. It is still the thing most often skipped. Budget a little time for it every quarter and it never becomes a project of its own.
Your first week
- Find out what is already in place
- Database changes are what make it complicated
- Change one thing and measure it
Practise the rollback before you need it. It is worth being explicit about, because assumptions differ quietly. Doing this properly once is usually cheaper than doing it approximately three times.
How to tell if yours is fine
Cloud work rewards teams who automate early and punishes teams who click through consoles. Three things worth confirming about blue-green deployment before you move on:
- Someone can say what the current setup is without going to look
- Practise the rollback before you need it — and you know whether that is true here
- There is a way to tell whether the last change to this helped
None of this needs a rewrite. Most of it is a morning's work once someone decides to do it.