kubernetes中的副本控制器rc(replicationcontrollers)和rs(replicasets)

news2024/9/22 11:30:29

一、rc控制器replicationcontrollers

rc控制器就是控制相同pod副本数量

使用rc控制器资源创建pod，设定创建pod资源的数量

1.1 案例

1.1.1、创建资源清单

[root@master rc-demo]# cat rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: rc01
spec:
replicas: 3 #控制要创建的副本数量
selector:
k8s: dolphin
template:
metadata:
name: pod-01
labels:
k8s: dolphin
spec:
containers:
- name: c1
image: nginx
ports:
- containerPort: 80

1.1.2、创建资源

[root@master rc-demo]# kubectl apply -f rc.yaml

1.1.3、查看资源

1.1.4、删除资源

[root@master rc-demo]# kubectl delete -f rc.yaml
replicationcontroller "rc01" deleted

1.1.5、总结

rc控制器创建的pod是按照标签进行父辈数量控制的；
rc控制器资源创建的pod，直接删除pod，还会重新拉起，只有删除rc资源，pod才会消失
修改rc资源，需要重新编辑rc资源清单，再次apply就可以修改了

1.2 rc控制器实现资源业务的升级与回滚

1.2.1 创建2个镜像的版本

第一个镜像

[root@master rc-demo]# cat Dockerfile
FROM nginx:1.20.1-alpine

RUN echo rc-v1 > /usr/share/nginx/html/index.html

CMD ["/usr/sbin/nginx", "-g", "daemon off;"]

[root@master rc-demo]# docker build -t dolphinc/nginx:v1 .
[root@master rc-demo]# docker push dolphinc/nginx:v1

第二个镜像

[root@master rc-demo]# cat Dockerfile
FROM nginx:1.20.1-alpine

RUN echo rc-v2 > /usr/share/nginx/html/index.html

CMD ["/usr/sbin/nginx", "-g", "daemon off;"]

[root@master rc-demo]# docker build -t dolphinc/nginx:v2 .
[root@master rc-demo]# docker push dolphinc/nginx:v2

1.2.2 编辑资源清单

[root@master rc-demo]# cat rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: rc-nginx
spec:

replicas: 3 #控制pod的副本数量
selector:
k8s: dolphinc-rc
#下面就是你要控制的pod了(就是pod资源的编辑)；
template:
metadata:
name: pod-nginx
labels:
k8s: dolphinc-rc
spec:
containers:
- name: c1
image: dolphinc/nginx:v1
ports:
- containerPort: 80
command:
- "nginx"
- "-g"
- "daemon off;"
---
#编辑service资源用于外部访问
apiVersion: v1
kind: Service
metadata:
name: svc-rc-nginx
spec:
type: NodePort
selector:
k8s: dolphinc-rc
ports:
- port: 88
targetPort: 80
nodePort: 30001

1.2.3 创建资源

[root@master rc-demo]# kubectl apply -f rc.yaml

1.2.4 查看资源

1.2.5 访问资源

1.2.6 修改rc.yaml 更换镜像

[root@master rc-demo]# cat rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: rc-nginx
spec:

replicas: 3 #控制pod的副本数量
selector:
k8s: dolphinc-rc
#下面就是你要控制的pod了(就是pod资源的编辑)；
template:
metadata:
name: pod-nginx
labels:
k8s: dolphinc-rc
spec:
containers:
- name: c1
image: dolphinc/nginx:v2
ports:
- containerPort: 80
command:
- "nginx"
- "-g"
- "daemon off;"
---
#编辑service资源用于外部访问
apiVersion: v1
kind: Service
metadata:
name: svc-rc-nginx
spec:
type: NodePort
selector:
k8s: dolphinc-rc
ports:
- port: 88
targetPort: 80
nodePort: 30001