k8s cookbook读书笔记 第二章

走一遍概念　　

• An overview of Kubernetes control
• f Working with pods
• f Working with a replication controller
• f Working with services
• f Working with volumes
• f Working with secrets
• f Working with names
• f Working with namespaces
• f Working with labels and selectors

1. An overview of Kubernetes control

查看k8s版本

　　% kubectl version

是如何做到的

　　kubectl通过restful api 连接kubernetes api server

如何工作的

　　kubectl [command] [TYPE] [NAME] [flags]

      /usr/local/bin/kubectl run my-first-nginx --image=nginx

      However, you can write either a YAML file or a JSON file to perform similar operations. 

# cat nginx.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: my-first-nginx
spec:
replicas: 1
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: my-first-nginx
image: nginx

Then specify the  create -f option to execute the  kubectl command as follows

# kubectl create -f nginx.yaml
replicationcontroller "my-first-nginx" created

 status of the replication controller

# kubectl get replicationcontrollers
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS AGE
my-first-nginx my-first-nginx nginx app=nginx 1 12s

 缩写

kubectl get rc
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS AGE
my-first-nginx my-first-nginx nginx app=nginx 1 1m

删除

# kubectl delete rc my-first-nginx
replicationcontroller "my-first-nginx" deleted

2.pods

   是k8s中最小的可部署单元

   每个pod被进程id，网络，进程间通信，时间命名空间隔离。

   docker pull centos

# cat my-first-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: my-first-pod
spec:
containers:
- name: my-nginx
image: nginx
- name: my-centos
image: centos
command: ["/bin/sh", "-c", "while : ;do curl http://
localhost:80/; sleep 3; done"]