ipedrazas / infracoders-meetup

material for the talk

infracoders-meetup

During this talk we will look at the Kuberentes Probes:

• LivenessProbe: I'm healthy. Keep sending traffic!
• ReadinessProbe: I'm ready. Start sending traffic!

Why and how should we use them.

There are 3 examples:

• Simple readinessProbe example with 1 pod and 2 containers: the idea is to highlight that the health check is per container, not per pod (important).
• Microservice B with a dependency to MongoDB and another microservice.
• Third example to illustrate how the readinessProbe can help to minimise errors.

A Probe is a diagnostic performed periodically by the kubelet on a container. Specifically the diagnostic is one of three Handlers:

• ExecAction: executes a specified command inside the container expecting on success that the command exits with status code 0.
• TCPSocketAction: performs a tcp check against the container’s IP address on a specified port expecting on success that the port is open.
• HTTPGetAction: performs an HTTP Get against the container’s IP address on a specified port and path expecting on success that the response has a status code greater than or equal to 200 and less than 400.