查询类
# custom-columns
# 比如 查看role=sre 标签pod镜像，当然也可以用go的自定义输出
kubectl -n kube-system get po -l tier=control-plane -o custom-columns=NAME:.metadata.name,image:.spec.containers[0].image
NAME image
etcd-ubuntu-bionic gcr.azk8s.cn/google_containers/etcd:3.3.15-0
kube-apiserver-ubuntu-bionic gcr.azk8s.cn/google_containers/kube-apiserver:v1.16.2
kube-controller-manager-ubuntu-bionic gcr.azk8s.cn/google_containers/kube-controller-manager:v1.16.2
kube-scheduler-ubuntu-bionic gcr.azk8s.cn/google_containers/kube-scheduler:v1.16.2
# go-template
# range 嵌套
# 列出所有容器使用的镜像名
kubectl get pods -o go-template --template='{{range .items}}{{range .spec.containers}}{{printf "%s\n" .image}}{{end}}{{end}}'
istio/examples-bookinfo-details-v1:1.5.0
istio/examples-bookinfo-productpage-v1:1.5.0
istio/examples-bookinfo-ratings-v1:1.5.0
# 条件判断
# 列出所有不可调度节点的节点名与 IP
kubectl get no -o go-template='{{range .items}}{{if .spec.unschedulable}}{{.metadata.name}} {{.spec.externalID}}{{"\n"}}{{end}}{{end}}'
# jsonpath
# 查询pod的启动时间
kubectl -n kube-system get pods -o=jsonpath='{range .items[*]}{.metadata.name}{"\t"}{.status.startTime}{"\n"}{end}'
coredns-667f964f9b-fs6kl 2019-12-25T02:54:20Z
coredns-667f964f9b-rlsr5 2019-12-25T02:54:20Z
etcd-ubuntu-bionic 2019-12-25T02:53:19Z
kube-apiserver-ubuntu-bionic 2019-12-28T06:25:42Z
kube-controller-manager-ubuntu-bionic 2019-12-28T06:25:43Z
kube-flannel-ds-amd64-jk586 2019-12-25T02:54:09Z
kube-proxy-vsjmv 2019-12-25T02:53:48Z
kube-scheduler-ubuntu-bionic 2019-12-28T06:25:43Z
jsonpath查询表
| Function | Description | Example | Result |
|---|---|---|---|
text |
the plain text | kind is {.kind} |
kind is List |
@ |
the current object | {@} |
the same as input |
. or [] |
child operator | {.kind}, {['kind']} or {['name\.type']} |
List |
.. |
recursive descent | {..name} |
127.0.0.1 127.0.0.2 myself e2e |
* |
wildcard. Get all objects | {.items[*].metadata.name} |
[127.0.0.1 127.0.0.2] |
[start🔚step] |
subscript operator | {.users[0].name} |
myself |
[,] |
union operator | {.items[*]['metadata.name', 'status.capacity']} |
127.0.0.1 127.0.0.2 map[cpu:4] map[cpu:8] |
?() |
filter | {.users[?(@.name=="e2e")].user.password} |
secret |
range, end |
iterate list | {range .items[*]}[{.metadata.name}, {.status.capacity}] {end} |
[127.0.0.1, map[cpu:4]] [127.0.0.2, map[cpu:8]] |
'' |
quote interpreted string | {range .items[*]}{.metadata.name}{'\t'}{end} |
127.0.0.1 127.0.0.2 |
补丁类
#Patch 把SVC改为NodePort类型
kubectl -n istio-system patch svc $SVC -p '{"spec":{"type":"NodePort"}}'
command: ['sh', '-c', 'echo Hello Kubernetes! && sleep 3600']
args:
- /bin/sh
- -c
- touch /tmp/healthy; sleep 30; rm -rf /tmp/healthy; sleep 60;
# 为Pod template 加上新label 打patch
kubectl patch deployment simple --type=json -p='[{"op": "add", "path": "/spec/template/metadata/labels/this", "value": "that"}]'
kubectl patch deployment myDeployment --patch '{"spec": {"template": {"metadata": {"labels": {"myLabelKey": "myLabelValue"}}}}}'
# 打pacth 使用文件
spec:
template:
spec:
containers:
- name: curl
image: nginx:alpine
env:
- name: key
value: value
# 修改po的container的镜像
kubectl patch deployment patch-demo --patch '{"spec": {"template": {"spec": {"containers": [{"name": "patch-demo-ctr-2","image": "redis"}]}}}}'
# 使 node 不可调度 当然cordon 也是可以的
kubectl patch node ${NAME} -p "{\"spec\":{\"unschedulable\":false}}"
# 官方的示例
Examples:
# Partially update a node using a strategic merge patch. Specify the patch as JSON.
kubectl patch node k8s-node-1 -p '{"spec":{"unschedulable":true}}'
# Partially update a node using a strategic merge patch. Specify the patch as YAML.
kubectl patch node k8s-node-1 -p $'spec:\n unschedulable: true'
# Partially update a node identified by the type and name specified in "node.json" using strategic merge patch.
kubectl patch -f node.json -p '{"spec":{"unschedulable":true}}'
# Update a container's image; spec.containers[*].name is required because it's a merge key.
kubectl patch pod valid-pod -p '{"spec":{"containers":[{"name":"kubernetes-serve-hostname","image":"new image"}]}}'
# Update a container's image using a json patch with positional arrays.
kubectl patch pod valid-pod --type='json' -p='[{"op": "replace", "path": "/spec/containers/0/image", "value":"new
image"}]'
快捷键
# 运行一个deployment
kubectl run nginx --image=nginx:alpine --replicas=1 --port=80
# 删除非running Pod
kubectl get pods --all-namespaces -ojson | jq -r '.items[] | select(.status.reason!=null) | select(.status.reason | contains("Evicted")) | .metadata.name + " " + .metadata.namespace' | xargs -n2 -l bash -c 'kubectl delete pods $0 --namespace=$1'
# 正则匹配某个pod
kubectl logs -n kube-system $(kubectl get po -n kube-system | egrep -o alb-ingress[a-zA-Z0-9-]+)
# 修改po的container的镜像 set image 方式
kubectl set image deploy -l run=nginx nginx=vsxen/k8s
deployment.extensions/nginx image updated
kubectl get rs
NAME DESIRED CURRENT READY AGE
nginx-5dbb4c75cd 1 1 1 7m
nginx-7444d44744 1 1 0 47s
externalTrafficPolicy: Cluster
externalIPs:
- 10.0.0.52