CentOS7 上yum安装k8s

1、环境准备

我这里的配置是一个master一个node节点

节点	服务器IP
master	10.10.100.131
node	10.10.100.139

2、安装配置

2.1 Master节点

服务端安装

yum -y install etcd kubernetes-master

服务端的配置文件在 /etc/kubernetes 里面，如下几个文件

# ls -lh /etc/kubernetes/
apiserver           config              controller-manager  scheduler

apiserver文件配置

###
# kubernetes system config
#
# The following values are used to configure the kube-apiserver
#

# The address on the local server to listen to.
KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"

# The port on the local server to listen on.
KUBE_API_PORT="--port=8080"

# Port minions listen on
KUBELET_PORT="--kubelet-port=10250"

# Comma separated list of nodes in the etcd cluster
KUBE_ETCD_SERVERS="--etcd-servers=http://127.0.0.1:2379"

# Address range to use for services
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"

# default admission control policies
# KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"

# Add your own!
KUBE_API_ARGS=""

config文件配置

# logging to stderr means we get it in the systemd journal
KUBE_LOGTOSTDERR="--logtostderr=true"

# journal message level, 0 is debug
KUBE_LOG_LEVEL="--v=0"

# Should this cluster be allowed to run privileged docker containers
KUBE_ALLOW_PRIV="--allow-privileged=false"

# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://127.0.0.1:8080"

启动服务和设置开机自启动

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

2.2 Node节点

软件安装

yum -y install flannel kubernetes-node

Node节点的配置主要有两个地方，一个在/etc/sysconfig/flanneld，另一个在/etc/kubernetes目录下

# ls /etc/kubernetes/
config  kubelet  proxy

flanneld配置

# Flanneld configuration options  

# etcd url location.  Point this to the server where etcd runs
FLANNEL_ETCD_ENDPOINTS="http://10.10.100.131:2379"

# etcd config key.  This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_PREFIX="/atomic.io/network"

# Any additional options that you want to pass
#FLANNEL_OPTIONS=""

config文件配置

# logging to stderr means we get it in the systemd journal
KUBE_LOGTOSTDERR="--logtostderr=true"

# journal message level, 0 is debug
KUBE_LOG_LEVEL="--v=0"

# Should this cluster be allowed to run privileged docker containers
KUBE_ALLOW_PRIV="--allow-privileged=false"

# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://10.10.100.131:8080"

kubelet文件配置

# The address for the info server to serve on (set to 0.0.0.0 or "" for all interfaces)
KUBELET_ADDRESS="--address=0.0.0.0"

# The port for the info server to serve on
KUBELET_PORT="--port=10250"

# You may leave this blank to use the actual hostname
KUBELET_HOSTNAME="--hostname-override=10.10.100.139"

# location of the api-server
KUBELET_API_SERVER="--api-servers=http://10.10.100.131:8080"

# pod infrastructure container
KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"

# Add your own!
KUBELET_ARGS="--logtostderr=false --v=0 --log-dir=/data/logs/kubernetes"

配置完成后，启动服务，并配置开机自启动

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

3、Master管理

可以看到node节点的状态和运行时间

# kubectl get node
NAME            STATUS    AGE
10.10.100.139   Ready     21h

3.1 创建Pod

新建nginx-pod.yml文件，内容如下：

apiVersion: v1
kind: Pod
metadata:
  name: nginx-pod
  labels:
    app: nginx
spec:
  containers:
    - name: nginx
      image: nginx
      imagePullPolicy: IfNotPresent
      ports:
        - containerPort: 80
          hostPort: 80

创建pod

kubectl create -f nginx-pod.yaml

创建完成后，运行命令查看pod的状态

# kubectl get pod
NAME        READY     STATUS    RESTARTS   AGE
nginx-pod   1/1       Running   0          20h

在node节点上运行 docker ps 就能够看到新建的容器了