Kubernetes Probes: A Hands-On Guide to Making Your Apps Resilient
How Kubernetes Probes Work
This interactive guide uses a browser-based Kubernetes simulator to demonstrate how startup, readiness, and liveness probes work. It shows how probes prevent request failures during rollouts, how to configure them properly, and how misconfiguration can cause crash loops. The author also shares a bug found in Kubernetes during testing.
It sounds like startup probes are best suited to the problem I showed you in the demos above, so let’s start there.
- stackskipton
SRE here, Strong disagree with do not fail readiness and liveness checks on upstream dependencies failing. There are several reason to do so and unless you have extreme start up time, what's the problem with restarting?
Maybe DNS has changed on you but you are stuck with bad local cache because you poorly respect TTLs (Looking at you Java), reseting the process will clear that cache away.
Maybe TCP connections are in stuck weird state, resetting the process generally helps with that.
Maybe someone gave you bad ENV VARs and you cannot connect to database, by refusing to progress the rollout, no outage generated.
So yea, if you are not ready to do work including critical upstream dependencies, don't lie to system and say you are.
- sidcool
This does not state anything new, but explains it so much well than the kubernetes documentation.
- stroebs
I need to know how to animate things like this for internal documentation.