在CentOS7中安装Kubernetes

一直以来都想尝鲜下Kubernates但是每次看网站都云里雾里的，在google中看到很多博客都写了安装的步骤，于是乎我就参考了Jimmy Song写的在CentOS上安装Kubernetes详细指南。这里写下安装的步骤记录一下。

kubernetesincentos

系统环境

  • CentOS Linux release 7.3.1611
  • Docker 17.03.1-ce
  • Etcd 3.1.5
  • Kubernetes 1.6.0
  • flannel 0.7.0-1

一. Master安装

  1. 关闭sellinux和防火墙

    echo "SELINUX=disabled
      SELINUXTYPE=targeted" > /etc/sysconfig/selinux
setenforce 0
systemctl stop firewalld
systemctl disable firewalld

  2. 打开文件限制

    echo "*                -       nofile          65536" >> /etc/security/limits.conf

  3. 安装docker

    curl -sSL https://get.docker.com/ | sh

  4. 安装配置etcd

    1. 下载安装包并将解压后的文件etcd,etcdctl放入/usr/bin/下

      DOWNLOAD_URL=https://storage.googleapis.com/etcd  
ETCD_VER=v3.1.5  
wget ${DOWNLOAD_URL}/${ETCD_VER}/etcd-${ETCD_VER}-linux-amd64.tar.gz
tar xvf etcd-${ETCD_VER}-linux-amd64.tar.gz
cd etcd-${ETCD_VER}-linux-amd64/
mv etcd etcdtl /usr/bin/

    2. 添加配置文件

      mkdir -p /etc/etcd/
touch /etc/etcd/etcd.conf
cat << ETCD_CONF >/etc/etcd/etcd.conf
# [member]
ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
# ETCD_WAL_DIR=""
# ETCD_SNAPSHOT_COUNT="10000"
# ETCD_HEARTBEAT_INTERVAL="100"
# ETCD_ELECTION_TIMEOUT="1000"
# ETCD_LISTEN_PEER_URLS="http://localhost:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
# ETCD_MAX_SNAPSHOTS="5"
# ETCD_MAX_WALS="5"
# ETCD_CORS=""
#
# [cluster]
# ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost:2380"
# if you use different ETCD_NAME (e.g. test), set ETCD_INITIAL_CLUSTER value for this name, i.e. "test=http://..."
# ETCD_INITIAL_CLUSTER="default=http://localhost:2380"
# ETCD_INITIAL_CLUSTER_STATE="new"
# ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://0.0.0.0:2379"
# ETCD_DISCOVERY=""
# ETCD_DISCOVERY_SRV=""
# ETCD_DISCOVERY_FALLBACK="proxy"
# ETCD_DISCOVERY_PROXY=""
#
# [proxy]
# ETCD_PROXY="off"
# ETCD_PROXY_FAILURE_WAIT="5000"
# ETCD_PROXY_REFRESH_INTERVAL="30000"
# ETCD_PROXY_DIAL_TIMEOUT="1000"
# ETCD_PROXY_WRITE_TIMEOUT="5000"
# ETCD_PROXY_READ_TIMEOUT="0"
#
# [security]
# ETCD_CERT_FILE=""
# ETCD_KEY_FILE=""
# ETCD_CLIENT_CERT_AUTH="false"
# ETCD_TRUSTED_CA_FILE=""
# ETCD_PEER_CERT_FILE=""
# ETCD_PEER_KEY_FILE=""
# ETCD_PEER_CLIENT_CERT_AUTH="false"
# ETCD_PEER_TRUSTED_CA_FILE=""
# [logging]
# ETCD_DEBUG="false"
# examples for -log-package-levels etcdserver=WARNING,security=DEBUG
# ETCD_LOG_PACKAGE_LEVELS=""
ETCD_CONF

    3. 创建etcd.service

      mkdir -p /var/lib/etcd
cat << ETCD_SERVICE > /usr/lib/systemd/system/etcd.service
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
WorkingDirectory=/var/lib/etcd/
EnvironmentFile=/etc/etcd/etcd.conf
# set GOMAXPROCS to number of processors
ExecStart=/bin/bash -c "GOMAXPROCS=$(nproc) /usr/bin/etcd --name=\"${ETCD_NAME}\" --data-dir=\"${ETCD_DATA_DIR}\" --listen-client-urls=\"${ETCD_LISTEN_CLIENT_URLS}\""
Restart=on-failure

[Install]
WantedBy=multi-user.target
ETCD_SERVICE

  5. 安装flannel

    yum install flannel -y

  6. 安装kubernetes

    1. 下载kubernetes并安装

      wget https://github.com/kubernetes/kubernetes/releases/download/v1.6.0/kubernetes.tar.gz
tar -zxvf kubernetes.tar.gz
cd kubernetes
./cluster/get-kube-binaries.sh
cd server
tar -xvf kubernetes-server-linux-amd64.tar.gz
cd kubernetes/bin
rm -f *_tag *.tar
chmod 755 *
mv * /usr/bin

    2. 配置kubernates

      Master节点需要配置的kubernetes的组件有:

      • kube-apiserver
      • kube-controller-manager
      • kube-scheduler
      • kube-proxy
      • kubectl
      1. 配置kube-apiserver
      #创建kube-apiserver的配置文件
touch /etc/kubernetes/apiserver
cat << KUBE_APISERVER > /etc/kubernetes/apiserver
###
## 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=${your_master_api_address}"
#
## The port on the local server to listen on.
KUBE_API_PORT="--insecure-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_ADDREKUBELET_POD_INFRA_CONTAINERSSES="--service-cluster-ip-range=10.254.0.0/16"
#
## default admission control policies
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"
#
## Add your own!
KUBE_API_ARGS=""
KUBE_APISERVER

#创建kube-apiserver的service文件
touch /usr/lib/systemd/system/kube-apiserver.service
cat << KUBE_APISERVER_SERVICE > /usr/lib/systemd/system/kube-apiserver.service
[Unit]
Description=Kubernetes API Service
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=network.target
After=etcd.service

[Service]
EnvironmentFile=/etc/kubernetes/config
EnvironmentFile=/etc/kubernetes/apiserver
ExecStart=/usr/bin/kube-apiserver \
	    $KUBE_LOGTOSTDERR \
	    $KUBE_LOG_LEVEL \
	    $KUBE_ETCD_SERVERS \
	    $KUBE_API_ADDRESS \
	    $KUBE_API_PORT \
	    $KUBE_ALLOW_PRIV \
	    $KUBE_SERVICE_ADDRESSES \
	    $KUBE_ADMISSION_CONTROL \
	    $KUBE_API_ARGS \
		$KUBE_SERVICE_ADDREKUBELET_POD_INFRA_CONTAINERSSES
Restart=on-failure
Type=notify

[Install]
WantedBy=multi-user.target
KUBE_APISERVER_SERVICE

      1. 配置kube-controller-manager

        # 创建kube-controller-manager配置文件
touch /etc/kubernetes/config
cat << KUBE_CONFIG > /etc/kubernetes
###
# kubernetes system config
#
# The following values are used to configure various aspects of all
# kubernetes services, including
#
#   kube-apiserver.service
#   kube-controller-manager.service
#   kube-scheduler.service
#   kubelet.service
#   kube-proxy.service
# 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://${your_master_api_address}:8080"
KUBE_CONFIG
touch /etc/kubernetes/controller-manager
cat << KUBE_CONTROLLER > /etc/kubernetes/controller-manmger
###
# The following values are used to configure the kubernetes controller-manager
# defaults from config and apiserver should be adequate
# Add your own!
KUBE_CONTROLLER_MANAGER_ARGS=""
KUBE_CONTROLLER
#创建kube-controller-manmger的service文件
touch /usr/lib/systemd/system/kube-controller-manmger.service
cat KUBE_CONTROLLER_SERVICE > /usr/lib/systemd/system/kube-controller-manmger.service
[unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
EnvironmentFile=/etc/kubernetes/config
EnvironmentFile=/etc/kubernetes/controller-manager
ExecStart=/usr/bin/kube-controller-manager \
	    $KUBE_LOGTOSTDERR \
	    $KUBE_LOG_LEVEL \
	    $KUBE_MASTER \
	    $KUBE_CONTROLLER_MANAGER_ARGS
Restart=on-failure
[Install]
WantedBy=multi-user.target
KUBE_CONTROLLER_SERVICE

      2. 配置kube-scheduler

        #创建kube-scheduler的配置文件
touch /etc/kubernetes/scheduler
cat << KUBE_SCHEDULER > /etc/kubernetes/scheduler
###
# kubernetes scheduler config
# default config should be adequate
# Add your own!
KUBE_SCHEDULER_ARGS=""
KUBE_SCHEDULER

#创建kube-scheduler的service文件
touch /usr/lib/systemd/system/kube-scheduler.service
cat << KUBE_SCHEDULER_SERVICE > /usr/lib/systemd/system/kube-scheduler.service
[Unit]
Description=Kubernetes Scheduler Plugin
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
EnvironmentFile=/etc/kubernetes/config
EnvironmentFile=/etc/kubernetes/scheduler
ExecStart=/usr/bin/kube-scheduler \
        $KUBE_LOGTOSTDERR \
        $KUBE_LOG_LEVEL \
        $KUBE_MASTER \
        $KUBE_SCHEDULER_ARGS
Restart=on-failure

[Install]
WantedBy=multi-user.target
KUBE_SCHEDULER_SERVICE

      3. 配置kube-proxy

        #创建kube-proxy的配置文件
touch /etc/kubernetes/proxy
cat << KUBE_PROXY > /etc/kubernetes/proxy
###
# kubernetes proxy config
# default config should be adequate
# Add your own!
KUBE_PROXY_ARGS=""
KUBE_PROXY
#创建kube-proxy的service文件
touch /usr/lib/systemd/system/kube-proxy.service
cat << KUBE_PROXY_SERVICE > /usr/lib/systemd/system/kube-proxy.service
[Unit]
Description=Kubernetes Kube-Proxy Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=network.target

[Service]
EnvironmentFile=/etc/kubernetes/config
EnvironmentFile=/etc/kubernetes/proxy
ExecStart=/usr/bin/kube-proxy \
	    $KUBE_LOGTOSTDERR \
	    $KUBE_LOG_LEVEL \
	    $KUBE_MASTER \
	    $KUBE_PROXY_ARGS
Restart=on-failure

[Install]
WantedBy=multi-user.target
KUBE_PROXY_SERVICE

      4. 配置kubelet

        #创建kubelet的配置文件
touch /etc/kubernetes/kubelet
cat << KUBELET > /etc/kubernetes/kubelet
###
## kubernetes kubelet (minion) config
#
## 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=${your_master_api_address}"
#
## location of the api-server
KUBELET_API_SERVER="--api_servers=http://${your_master_api_address}: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=""
KUBELET

#创建kubelet的service文件
touch /usr/lib/systemd/system/kubelet.service
cat << KUBELET_SERVICE > /usr/lib/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=docker.service
Requires=docker.service

[Service]
WorkingDirectory=/var/lib/kubelet
EnvironmentFile=/etc/kubernetes/config
EnvironmentFile=/etc/kubernetes/kubelet
ExecStart=/usr/bin/kubelet \
	    $KUBE_LOGTOSTDERR \
	    $KUBE_LOG_LEVEL \
	    $KUBELET_API_SERVER \
	    $KUBELET_ADDRESS \
	    $KUBELET_PORT \
	    $KUBELET_HOSTNAME \
	    $KUBE_ALLOW_PRIV \
	    $KUBELET_POD_INFRA_CONTAINER \
	    $KUBELET_ARGS
Restart=on-failure

[Install]
WantedBy=multi-user.target
KUBELET_SERVICE

    3. 启动kubernetes master

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

    4. 在master上验证kubernetes

      #如果你的master用的是IP，那就得先运行
alias kubectl=" kubectl -s http://${your_master_api_address}:8080"
#然后就可以运行
kubectl get all
#运行后一般会有这样的结果
NAME             CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
svc/kubernetes   10.254.0.1   <none>        443/TCP   2h