Reviewing cluster logs

We explained that the kube-system namespace is a Kubernetes namespace reserved for system-level components. It hosts essential system services like networking, monitoring, and storage management. Components in this namespace ensure the proper functioning and management of the Kubernetes cluster. We then explained the components of our kube-system below.

  • etcd: This component is the distributed key-value store for Kubernetes, storing essential configuration data and the cluster’s current state.

  • kindnet: This component is a Kubernetes network plugin responsible for managing networking within the cluster.

  • coredns: This component is Kubernetes’ DNS server, translating service and pod names to IP addresses for seamless communication.

  • kube-apiserver: This component acts as the central control point for the Kubernetes API. It exposes the API to users, applications, and other components, allowing them to interact with the cluster.

  • kube-controller-manager: This component houses various controllers that observe the state of the cluster and work to ensure the desired state is maintained. 

  • kube-proxy: This component is a network proxy service responsible for load balancing and routing network traffic within the cluster.

  • kube-scheduler: This component is responsible for making intelligent decisions about where to place Pods within the cluster based on factors like resource requirements, affinity rules, and node availability.

We highlighted checking events in a cluster using the kubectl get events command on our cluster, to get all the events of what’s happening within our environment. We concluded by using the --field-selector flag for filtering events by namespace and object.

Analyzing logs on pod and node

We discussed how we can analyze logs on a node level, by navigating to the container path and viewing them. We also discussed how to analyze logs in various containers running within a pod using the -c flag. We list the full command below.

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