Kubernetes

Useful

alias:

alias k="kubectl"
alias ks="kubectl --namespace kube-system"

dump all :

kubectl get all --export=true -o yaml

list form:

k get pods
k get rs # replica set
k get rc # replication controller

what are all the things ?

kubectl api-resources

event sorted by time

kubectl get events --sort-by=.metadata.creationTimestamp

what storage classes does my cluster support?

k get storageclass

metricss

wget "$(kubectl config view -o jsonpath='{range .clusters[*]}{@.cluster.server}{"\n"}{end}')"

Practices and Guidlines

Do not use replication controllers, instead use replica sets

Cgroup / slice errors

https://github.com/kubernetes/kubernetes/issues/56850

log message:

Sep 18 21:32:37 ip-10-10-37-50 kubelet[1681]: E0918 21:32:37.901058    1681 summary.go:92] Failed to get system container stats for "/system.slice/docker.service": failed to get cgroup stats for "/system.slice/docker.service": failed to get container info for "/system.slice/docker.service": unknown container "/system.slice/docker.service"