1. Labels 1.1 What Labels Are Labels are key-value pairs attached to an object. You can add labels directly when the object is created, or modify them dynamically afterwards. Label format: 1 2 3 4 "labels": { "key1" : "value1", "key2" : "value2" } Format requirements: Key: must be unique Value: must start with a letter or a digit, may contain letters, digits, hyphens, dots, and underscores, and is at most 63 characters long 1.

1. Docker’s Network Model 1.1 bridge Mode bridge mode is used by default, and you can also specify it with --net=bridge. In bridge mode, containers connect to the same virtual bridge, docker0. docker0 usually occupies the 172.17.0.1/16 subnet. Containers on the same bridge can communicate directly over IP. 1.2 host Mode Use --net=host to specify host mode.

Helm is the package manager for Kubernetes; Operator is used to manage stateful distributed applications on Kubernetes. This article mainly describes how to use Helm and Operator to quickly deploy Prometheus on a Minikube cluster and use Grafana to view monitoring data. For Minikube installation, see Building a Remote Kubernetes Development Environment; for Helm configuration, see The Package Manager for Kubernetes – Helm; for Operator, see Kubernetes Complex Stateful Application Management Framework – Operator.

1. Objects in Kubernetes Kubernetes objects are persistent entities in the system, used to represent the state of the cluster. Users interact with Kubernetes by operating on objects, telling the system the workload they expect. Objects are manipulated through the Kubernetes API. Every Kubernetes object contains two nested object fields, Spec and Status.

1. Origins Originally, two CoreOS employees, in order to make deploying etcd clusters easier, bound corresponding logical operations to the create, delete, and update events of the etcdCluster object, using Kubernetes to automate etcd cluster management. A few months later, at a KubeCon conference, they shared this approach, which they called Operator, and it received a strong response from the community.