There’s a reactive way to manage infrastructure and there’s a proactive way. The reactive way is: traffic increases, you notice the service is suffering, you add resources. The proactive way is: you understand your system well enough that it handles demand changes automatically, without you needing to be in the loop.

I prefer the lazy way.

Contrary to popular belief, monitoring an infrastructure is the opposite of just having some metrics about applications and network.

There are many excellent resources on this topic. One of the most interesting is just a few pages from Google — the art of SLOs. I took the book version from a Google on-site deep dive.

To structure this properly, I want to use four simple statements:

• WHAT
• WHY
• WHO
• HOW

WHAT

This is probably the main argument we’ll discuss here.