CentOS7.0上部署kubernetes集群 + 简单应用示例

master包含kube-apiserver kube-scheduler kube-controller-manager etcd四个组件

node包含kube-proxy和kubelet两个组件

关闭防火墙

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$ systemctl stop firewalld
$ systemctl disable firewalld

安装NTP

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$ yum -y install ntp
$ systemctl start ntpd
$ systemctl enable ntpd

部署Master

安装etcd和kubernetes

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$ yum -y install etcd kubernetes

配置etcd

/etc/etcd/etcd.conf

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ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"

配置etcd中的网络

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$ etcdctl mk /coreos.com/network/config '{"Network":"172.17.0.0/16"}'

配置Kubernetes API server

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API_ADDRESS="--address=0.0.0.0"
KUBE_API_PORT="--port=8080"
KUBELET_PORT="--kubelet_port=10250"
KUBE_ETCD_SERVERS="--etcd_servers=http://10.0.222.2:2379"
KUBE_SERVICE_ADDRESSES="--portal_net=10.254.0.0/16"
KUBE_ADMISSION_CONTROL="--admission_control=NamespaceLifecycle,
NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"
KUBE_API_ARGS=""

KUBE_ADMISSION_CONTROL

ServiceAccount

启动服务

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$for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do
systemctl restart $SERVICES
systemctl enable $SERVICES
systemctl status $SERVICES
done

部署Node

安装Kubernetes和Flannel

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$ yum -y install flannel kubernetes

配置Flannel

/etc/sysconfig/flanneld

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FLANNEL_ETCD="http://10.0.222.2:2379"
FLANNEL_ETCD_KEY="/coreos.com/network"
FLANNEL_OPTIONS="--iface=ens3"

FLANNEL_OPTIONS

启动Flannel

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$systemctl restart flanneld
$systemctl enable flanneld
$systemctl status flanneld

上传网络配置

config.json

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{
"Network": "172.17.0.0/16",
"SubnetLen": 24,
"Backend": {
"Type": "vxlan",
"VNI": 7890
}
}

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$ curl -L http://10.0.222.2:2379/v2/keys/coreos.com/network/config -XPUT --data-urlencode value@config.json

修改Kubernetes配置

/etc/kubernetes/config

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KUBE_MASTER="--master=http://10.0.222.2:8080"

修改kubelet配置

/etc/kubernetes/kubelet

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KUBELET_ADDRESS="--address=0.0.0.0"
KUBELET_PORT="--port=10250"
# change the hostname to minion IP address
KUBELET_HOSTNAME="--hostname_override=node1"
KUBELET_API_SERVER="--api_servers=http://10.0.222.2:8080"
KUBELET_ARGS=""

启动node服务

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$ for SERVICES in kube-proxy kubelet docker; do
systemctl restart $SERVICES
systemctl enable $SERVICES
systemctl status $SERVICES
done

创建快照，其他节点用快照安装（修改相应的hostname以及KUBELET_HOSTNAME即可）

查看集群nodes

#cat nginx-rc.yaml
apiVersion: v1kind: ReplicationController
metadata:
name: nginx-controller
spec:
replicas: 2
selector:
name: nginx
template:
metadata:
labels:
name: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80

[root@master test]# kubectl create -f nginx-rc.yaml
replicationcontrollers/nginx-controller

[root@master test]# kubectl get pods
NAME                     READY     STATUS    RESTARTS   AGE
nginx                    1/1       Running   0          1d
nginx-controller-dkl3v   1/1       Running   0          14s
nginx-controller-hxcq8   1/1       Running   0          14s

[root@master test]# kubectl describe pod nginx-controller-dkl3v
Name:				nginx-controller-dkl3v
Namespace:			default
Image(s):			nginx
Node:				192.168.32.17/192.168.32.17
Labels:				name=nginx
Status:				Running
Reason:
Message:
IP:				172.17.67.2
Replication Controllers:	nginx-controller (2/2 replicas created)
Containers:
nginx:
Image:		nginx
State:		Running
Started:		Wed, 30 Dec 2015 02:03:19 -0500
Ready:		True
Restart Count:	0
Conditions:
Type		Status
Ready 	True
Events:
FirstSeen				LastSeen			Count	From			SubobjectPath			Reason		Message
Wed, 30 Dec 2015 02:03:14 -0500	Wed, 30 Dec 2015 02:03:14 -0500	1	{scheduler }						scheduled	Successfully assigned nginx-controller-dkl3v to 192.168.32.17
Wed, 30 Dec 2015 02:03:15 -0500	Wed, 30 Dec 2015 02:03:15 -0500	1	{kubelet 192.168.32.17}	implicitly required container POD	pulled		Pod container image "kubernetes/pause" already present on machine
Wed, 30 Dec 2015 02:03:16 -0500	Wed, 30 Dec 2015 02:03:16 -0500	1	{kubelet 192.168.32.17}	implicitly required container POD	created		Created with docker id e88dffe46a28
Wed, 30 Dec 2015 02:03:17 -0500	Wed, 30 Dec 2015 02:03:17 -0500	1	{kubelet 192.168.32.17}	implicitly required container POD	started		Started with docker id e88dffe46a28
Wed, 30 Dec 2015 02:03:18 -0500	Wed, 30 Dec 2015 02:03:18 -0500	1	{kubelet 192.168.32.17}	spec.containers{nginx}		created		Created with docker id 25fcb6b4ce09
Wed, 30 Dec 2015 02:03:19 -0500	Wed, 30 Dec 2015 02:03:19 -0500	1	{kubelet 192.168.32.17}	spec.containers{nginx}		started		Started with docker id 25fcb6b4ce09

#cat nginx-service-clusterip.yaml
apiVersion: v1kind: Service
metadata:
name: nginx-service-clusterip
spec:
ports:
- port: 8001targetPort: 80
protocol: TCP
selector:
name: nginx

[root@master test]# kubectl create -f ./nginx-service-clusterip.yaml
services/nginx-service-clusterip

[root@master test]# kubectl get service
NAME                      LABELS                                    SELECTOR     IP(S)            PORT(S)
kubernetes                component=apiserver,provider=kubernetes   <none>       10.254.0.1       443/TCP
nginx-service-clusterip   <none>                                    name=nginx   10.254.234.255   8001/TCP

[root@minion1 ~]# curl -s 10.254.234.255:8001<!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>

cat nginx-service-nodeport.yaml
apiVersion: v1kind: Service
metadata:
name: nginx-service-nodeport
spec:
ports:
- port: 8000
targetPort: 80
protocol: TCP
type: NodePort
selector:
name: nginx

[root@master test]# kubectl create -f ./nginx-service-nodeport.yaml
You have exposed your service on an external port on all nodes in your
cluster.  If you want to expose this service to the external internet, you may
need to set up firewall rules for the service port(s) (tcp:31000) to serve traffic.

See http://releases.k8s.io/HEAD/docs/user-guide/services-firewalls.md for more details.
services/nginx-service-nodeport

[root@master test]# kubectl get service
NAME                      LABELS                                    SELECTOR     IP(S)            PORT(S)
kubernetes                component=apiserver,provider=kubernetes   <none>       10.254.0.1       443/TCP
nginx-service-clusterip   <none>                                    name=nginx   10.254.234.255   8001/TCP
nginx-service-nodeport    <none>                                    name=nginx   10.254.210.68    8000/TCP

[root@master test]# kubectl describe service nginx-service-nodeport
Name:			nginx-service-nodeport
Namespace:		default
Labels:			<none>
Selector:		name=nginx
Type:			NodePort
IP:			10.254.210.68
Port:			<unnamed>	8000/TCP
NodePort:		<unnamed>	31000/TCP
Endpoints:		172.17.67.2:80,172.17.67.3:80
Session Affinity:	None
No events.

[root@master test]# curl -s 192.168.32.16:31000
<!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@master test]# curl -s 192.168.32.17:31000
<!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>