Return HTTP status codes based on an arbitrary script

3 min read

Sometimes we need a way of telling using a HTTP endpoint the readiness of the service but the service does not provide any of this: For example, a MySQL replica that we need to get in and out of the pool depending on how lagged it is, or a worker node that we want to remove from that pool depending on it's CPU usage...

If we have a command that will tell us whether the service is ready to accept connections, we can use healthcheckd to create a HTTP endpoint to publish it.

27/10/2021

Kubernetes readinessProbe: testing container's availability

1 min read

Some applications might temporally not being able to server traffic due to some work it is doing: For example, loading data, contacting with external services... If we want to have a way to temporally disable traffic without restarting the application we will need to configure a readinessProbe

24/08/2021

Kubernetes livenessProbe: testing container's health

2 min read

Every application will, eventually, fail. In order to detect that the container is failing and being able to recover this situation by restarting it we can use the livenessProbe.

23/08/2021

Kubernetes startupProbe: testing containers for application startup

2 min read

Starting from Kubernetes v1.20 we can configure a startup Probe: It will check for containers to be come into service, disabling liveness and readiness checks until it succeeds.

05/08/2021