一、kubectl陈述式管理方法
kubectl小洁：
kubectl是官方的CLI命令行工具，用于apiserver进行通信，将用户在命令行输入的命令，组织并转化为apiserver能识别的信息，进而实现管理k8s各种资源的一种有效途径。
1、查看当前集群所有命名空间
[root@test-nodes1 ~]# kubectl get namespace
NAME STATUS AGE
default Active 42h
kube-node-lease Active 42h
kube-public Active 42h
kube-system Active 42h
2、查看default命名空间下的所有资源
[root@test-nodes1 ~]# kubectl get all -n default
NAME READY STATUS RESTARTS AGE
pod/nginx-ds-76fr8 0/1 ImagePullBackOff 0 39h
pod/nginx-ds-zz7jn 0/1 ErrImagePull 0 39h
pod/nginx-ds1-qg45q 1/1 Running 0 39h
pod/nginx-ds1-whnmv 1/1 Running 0 39h
#pod资源
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 42h
#service资源
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE
daemonset.apps/nginx-ds 2 2 0 2 0 <none> 39h
daemonset.apps/nginx-ds1 2 2 2 2 2 <none> 39h
#pod控制器
3、创建与删除命名空间
[root@test-nodes1 ~]# kubectl create namespace test
namespace/test created
[root@test-nodes1 ~]# kubectl get namespace
NAME STATUS AGE
default Active 42h
kube-node-lease Active 42h
kube-public Active 42h
kube-system Active 42h
test Active 6s
[root@test-nodes1 ~]# kubectl delete namespace test
namespace "test" deleted
4、创建deployment（pods控制器)资源
[root@test-nodes1 ~]# kubectl create deployment nignx-dp --image=test-harbor.cedarhd.com/public/nginx:v1.7.9 -n kube-public
deployment.apps/nignx-dp created
5、查看kube-public命名空间下的deployment资源控制器
[root@test-nodes1 ~]# kubectl get deployment -n kube-public
NAME READY UP-TO-DATE AVAILABLE AGE
nignx-test 0/1 1 0 70s
6、查看kube-public命名空间下pods的运行情况
[root@test-nodes1 ~]# kubectl get deployment -n kube-public
NAME READY UP-TO-DATE AVAILABLE AGE
nignx-test 1/1 1 1 21s
7、查看kube-public空间下的pods资源
[root@test-nodes1 ~]# kubectl get pods -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nignx-dp-7f6d4979bd-nnc57 0/1 ImagePullBackOff 0 13m 172.7.21.4 test-nodes1.cedarhd.com <none> <none>
nignx-test-655d6fbcb5-r9t57 1/1 Running 0 4m1s 172.7.22.4 test-nodes2.cedarhd.com <none> <none>
8、在test-nodes2.cedarhd.com节点上curl 172.7.22.4 nginx
[root@test-nodes2 ~]# curl 172.7.22.4
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
9、查看deployment下具体pods（nginx-test）详细信息
[root@test-nodes1 ~]# kubectl describe deployment nignx-test -n kube-public
Name: nignx-test
Namespace: kube-public
CreationTimestamp: Mon, 03 Feb 2020 02:02:59 -0500
Labels: app=nignx-test
Annotations: deployment.kubernetes.io/revision: 1
Selector: app=nignx-test
Replicas: 1 desired | 1 updated | 1 total | 1 available | 0 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: app=nignx-test
Containers:
nginx:
Image: test-harbor.cedarhd.com/public/nginx:v1.7.9
Port: <none>
Host Port: <none>
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available True MinimumReplicasAvailable
Progressing True NewReplicaSetAvailable
OldReplicaSets: <none>
NewReplicaSet: nignx-test-655d6fbcb5 (1/1 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 22m deployment-controller Scaled up replica set nignx-test-655d6fbcb5 to 1
10、进入nginx-test pod资源
[root@test-nodes1 ~]# kubectl get pods -n kube-public
NAME READY STATUS RESTARTS AGE
nignx-test-655d6fbcb5-r9t57 1/1 Running 0 24m
[root@test-nodes1 ~]# kubectl exec -ti nignx-test-655d6fbcb5-r9t57 /bin/bash -n kube-public
#与docker 操作方法一致
root@nignx-test-655d6fbcb5-r9t57:/# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
12: eth0@if13: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP
link/ether 02:42:ac:07:16:04 brd ff:ff:ff:ff:ff:ff
inet 172.7.22.4/24 brd 172.7.22.255 scope global eth0
valid_lft forever preferred_lft forever
11、删除pod资源（即重启）
[root@test-nodes1 ~]# kubectl delete pod nignx-test-655d6fbcb5-r9t57 -n kube-public
pod "nignx-test-655d6fbcb5-r9t57" deleted
[root@test-nodes1 ~]# kubectl get pods -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nignx-dp-7f6d4979bd-nnc57 0/1 ImagePullBackOff 0 40m 172.7.21.4 test-nodes1.cedarhd.com <none> <none>
nignx-test-655d6fbcb5-c42z8 1/1 Running 0 18s 172.7.21.5 test-nodes1.cedarhd.com <none> <none>
12、删除deployment
[root@test-nodes1 ~]# kubectl get deploy -n kube-public
NAME READY UP-TO-DATE AVAILABLE AGE
nignx-dp 0/1 1 0 53m
nignx-test 1/1 1 1 36m
[root@test-nodes1 ~]# kubectl delete deploy nignx-dp -n kube-public
deployment.extensions "nignx-dp" deleted
13、为nginx-dp pod资源创建service资源，保障pod的高可用,通过集群IP访问
[root@test-nodes1 ~]# kubectl get all -n kube-public
NAME READY STATUS RESTARTS AGE
pod/nginx-dp-5b9b697bcc-jtrlp 1/1 Running 0 17s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-dp 1/1 1 1 17s
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-dp-5b9b697bcc 1 1 1 17s
[root@test-nodes1 ~]# kubectl get pods -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dp-5b9b697bcc-jtrlp 1/1 Running 0 3m19s 172.7.21.4 test-nodes1.cedarhd.com <none> <none>
[root@test-nodes1 ~]# kubectl expose deployment nginx-dp --port=80 -n kube-public
service/nginx-dp exposed
[root@test-nodes1 ~]# kubectl get svc -n kube-public #查看service资源
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx-dp ClusterIP 192.168.224.56 <none> 80/TCP 12m
[root@test-nodes1 ~]# kubectl get all -n kube-public
NAME READY STATUS RESTARTS AGE
pod/nginx-dp-5b9b697bcc-jtrlp 1/1 Running 0 5m21s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/nginx-dp ClusterIP 192.168.224.56 <none> 80/TCP 79s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-dp 1/1 1 1 5m21s
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-dp-5b9b697bcc 1 1 1 5m21s
[root@test-nodes1 ~]# curl 192.168.224.56
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
[root@test-nodes1 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.0.1:443 nq
-> 10.3.153.221:6443 Masq 1 0 0
-> 10.3.153.222:6443 Masq 1 0 0
TCP 192.168.224.56:80 nq
-> 172.7.21.4:80 Masq 1 0 0 来源：51CTO
作者：wx592bc92b285c7
链接：https://blog.51cto.com/12965094/2468947