Let's first start by answering the question, "What is a check?" A check is a fundamental building block that either determines the status of, or gathers metrics from a system. So we have "status" checks and "metric" checks.
Let's take a look at an example status check configuration:
api_version: core/v2 type: CheckConfig metadata: namespace: default name: check-cpu spec: command: check-cpu.sh -w 75 -c 90 subscriptions: - system handlers: - slack publish: true interval: 60
Here, we're running a command to check our CPU utilization to see if it rises above a given threshold. Let's dissect this check.