Adobe acquired Magento for $1.67 billion, Microsoft acquired GitHub for $7.5 billion, IBM acquired Red Hat for $34 billion — open source turns out to be a good business too. This article is mainly a record of, and some thoughts about, open source. 1. What Open Source Is 1.1 History In 1969, Bell Labs shared the Unix source code with the community, laying an important foundation for open source.

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.