Compiled from the “Development Tips” series, gathering the common problems and solutions from day-to-day Kubernetes cluster operations. 1. Configuring Multiple Clusters with Kubectl When doing Kubernetes-related development you usually end up managing several clusters. Kubectl provides multi-cluster context management. Kubectl’s configuration usually lives in $HOME/.kube/config or /etc/kubernetes/admin.conf. Log into the machine, look at the cluster configuration, and edit it using the format below.

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.

1. Why Helm Is Needed One important design philosophy in Kubernetes is declarative operation. Users change the system by setting the system’s expected state. For example, the current replica count is 2 and it needs to be adjusted to 3. The declarative way is to modify the replica count in