一、部署说明

1.节点
master1: IP:192.168.0.170/24 hostname：171
master2: IP:192.168.0.171/24 hostname：172
VIP:192.168.0.169/24

2.工具版本：
etcd-v3.1.10-linux-amd64.tar.gz
kubeadm-1.9.0-0.x86_64.rpm
kubectl-1.9.0-0.x86_64.rpm
kubelet-1.9.9-9.x86_64.rpm
kubernetes-cni-0.6.0-0.x86_64.rpm
socat-1.7.3.2-2.el7.x86_64.rpm

docker离线镜像：
etcd-amd64_v3.1.10.tar
k8s-dns-dnsmasq-nanny-amd64_v1.14.7.tar
k8s-dns-kube-dns-amd64_1.14.7.tar
k8s-dns-sidecar-amd64_1.14.7.tar
kube-apiserver-amd64_v1.9.0.tar
kube-controller-manager-amd64_v1.9.0.tar
kube-proxy-amd64_v1.9.0.tar
kubernetes-dashboard_v1.8.1.tar
kube-scheduler-amd64_v1.9.0.tar
pause-amd64_3.0.tar

以上安装包的云盘链接随后附上.有梯子翻墙的直接装，无需离线包。

=================================================
k8s 高可用2个核心 apiserver master和etcd

apiserver master：（需高可用）集群核心，集群API接口、集群各个组件通信的中枢；集群安全控制；

etcd ：（需高可用）集群的数据中心，用于存放集群的配置以及状态信息，非常重要，如果数据丢失那么集群将无法恢复；因此高可用集群部署首先就是etcd是高可用集群；
kube-scheduler：调度器 （内部自选举）集群Pod的调度中心；默认kubeadm安装情况下–leader-elect参数已经设置为true，保证master集群中只有一个kube-scheduler处于活跃状态；

kube-controller-manager： 控制器（内部自选举）集群状态管理器，当集群状态与期望不同时，kcm会努力让集群恢复期望状态，比如：当一个pod死掉，kcm会努力新建一个pod来恢复对应replicasset期望的状态；默认kubeadm安装情况下–leader-elect参数已经设置为true，保证master集群中只有一个kube-controller-manager处于活跃状态；

kubelet: 将agent node注册上apiserver

kube-proxy: 每个node上一个，负责service vip到endpoint pod的流量转发，老版本主要通过设置iptables规则实现，新版1.9基于kube-proxy-lvs 实现

二、提前准备

1.关闭防火墙，selinux，swap

systemctl stop firewalld
systemctl disable firewalld
systemctl disable firewalld

setenforce 0
sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/sysconfig/selinux 
sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config 
sed -i "s/^SELINUX=permissive/SELINUX=disabled/g" /etc/sysconfig/selinux 
sed -i "s/^SELINUX=permissive/SELINUX=disabled/g" /etc/selinux/config 

swapoff -a
echo 'swapoff -a ' >> /etc/rc.d/rc.local

2.内核开启网络支持

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl -p /etc/sysctl.conf

若执行sysctl -p 时报错，尝试：

modprobe br_netfilter
ls /proc/sys/net/bridge

三、配置keepalived

yum -y install keepalived 

# 192.168.0.170配置
cat >/etc/keepalived/keepalived.conf  <<EOF
global_defs {
  router_id LVS_k8s
}

vrrp_script CheckK8sMaster {
    #修改为本机IP
    script "curl -k https://192.168.0.170:6443"
    interval 3
    timeout 5
    weight 11
    fall 3
    rise 2
}


vrrp_instance VI_0 {
    # 统一默认设置为BACKUP状态，成员会根据优先级值来自协商状态
    state BACKUP  
    interface eth0
    virtual_router_id 80
    # 主节点权重最高 依次减少
    priority 110

    advert_int 1
    #修改为本地IP
    mcast_src_ip 192.168.0.170

    track_interface {
        eth0
    }
    authentication {
        auth_type PASS
        auth_pass yks888
    }
    unicast_peer {
        #注释掉本地IP
        #192.168.0.170
        192.168.0.171
    }
    virtual_ipaddress {
        192.168.0.169/24
    }
    track_script {
        CheckK8sMaster
    }
}
EOF

# 192.168.0.171配置
cat >/etc/keepalived/keepalived.conf  <<EOL

global_defs {
  router_id LVS_k8s
}

vrrp_script CheckK8sMaster {
    #修改为本机IP
    script "curl -k https://192.168.0.171:6443"
    interval 3
    timeout 5
    weight 11
    fall 3
    rise 2
}


vrrp_instance VI_0 {
    # 统一默认设置为BACKUP状态，成员会根据优先级值来自协商状态
    state BACKUP  
    interface eth0
    virtual_router_id 80
    # 主节点权重最高 依次减少
    priority 100

    advert_int 1
    #修改为本地IP
    mcast_src_ip 192.168.0.171

    track_interface {
        eth0
    }
    authentication {
        auth_type PASS
        auth_pass yks888
    }
    unicast_peer {
        #注释掉本地IP
        192.168.0.170
        #192.168.0.171
    }
    virtual_ipaddress {
        192.168.0.169/24
    }
    track_script {
        CheckK8sMaster
    }
}
EOF
systemctl enable keepalived && systemctl restart keepalived

检查vip是否正常漂在master1上：

[root@170 pkgs]# ip a
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
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:1c:5d:71 brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.170/24 brd 192.168.0.255 scope global ens33
       valid_lft forever preferred_lft forever
    inet 192.168.0.169/24 scope global secondary ens33
       valid_lft forever preferred_lft forever

四、etcd配置

1.配置环境变量：

export NODE_NAME=170 #当前部署的机器名称(随便定义，只要能区分不同机器即可)
export NODE_IP=192.168.0.170 # 当前部署的机器 IP
export NODE_IPS="192.168.0.170 192.168.0.171 " # etcd 集群所有机器 IP
# etcd 集群间通信的IP和端口
export ETCD_NODES="170"=https://192.168.0.170:2380,"171"=https://192.168.0.171:2380

2.创建ca和证书和秘钥

wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64
chmod +x cfssl_linux-amd64
mv cfssl_linux-amd64 /usr/local/bin/cfssl

wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64
chmod +x cfssljson_linux-amd64
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson

wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64
chmod +x cfssl-certinfo_linux-amd64
mv cfssl-certinfo_linux-amd64 /usr/local/bin/cfssl-certinfo

生成ETCD的TLS 秘钥和证书
为了保证通信安全，客户端(如 etcdctl) 与 etcd 集群、etcd 集群之间的通信需要使用 TLS 加密，本节创建 etcd TLS 加密所需的证书和私钥。
创建 CA 配置文件：

cat >  ca-config.json <<EOF
{
"signing": {
"default": {
  "expiry": "87600h"
},
"profiles": {
  "kubernetes": {
    "usages": [
        "signing",
        "key encipherment",
        "server auth",
        "client auth"
    ],
    "expiry": "87600h"
  }
}
}
}
EOF

ca-config.json：可以定义多个 profiles，分别指定不同的过期时间、使用场景等参数；后续在签名证书时使用某个 profile；
signing：表示该证书可用于签名其它证书；生成的 ca.pem 证书中 CA=TRUE；
server auth：表示 client 可以用该 CA 对 server 提供的证书进行验证；
client auth：表示 server 可以用该 CA 对 client 提供的证书进行验证；

cat >  ca-csr.json <<EOF
{
"CN": "kubernetes",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
  "C": "CN",
  "ST": "BeiJing",
  "L": "BeiJing",
  "O": "k8s",
  "OU": "System"
}
]
}
EOF

“CN”：Common Name，kube-apiserver 从证书中提取该字段作为请求的用户名 (User Name)；浏览器使用该字段验证网站是否合法；
“O”：Organization，kube-apiserver 从证书中提取该字段作为请求用户所属的组 (Group)；
生成 CA 证书和私钥：

cfssl gencert -initca ca-csr.json | cfssljson -bare ca
ls ca*

创建 etcd 证书签名请求：

cat > etcd-csr.json <<EOF
{
  "CN": "etcd",
  "hosts": [
    "127.0.0.1",
    "192.168.0.170",
    "192.168.0.171"
  ],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "BeiJing",
      "L": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF

hosts 字段指定授权使用该证书的 etcd 节点 IP；
每个节点IP 都要在里面 或者 每个机器申请一个对应IP的证书
生成 etcd 证书和私钥：

cfssl gencert -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes etcd-csr.json | cfssljson -bare etcd

ls etcd*

mkdir -p /etc/etcd/ssl
cp etcd.pem etcd-key.pem  ca.pem /etc/etcd/ssl/

将生成的私钥文件分发到master2上：

scp -r /etc/etcd/ssl root@192.168.0.171:/etc/etcd/

3.安装etcd

wget http://github.com/coreos/etcd/releases/download/v3.1.10/etcd-v3.1.10-linux-amd64.tar.gz
tar -xvf etcd-v3.1.10-linux-amd64.tar.gz
mv etcd-v3.1.10-linux-amd64/etcd* /usr/local/bin
mkdir -p /var/lib/etcd  # 必须先创建工作目录


cat > etcd.service <<EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
Documentation=https://github.com/coreos

[Service]
Type=notify
WorkingDirectory=/var/lib/etcd/
ExecStart=/usr/local/bin/etcd \\
  --name=${NODE_NAME} \\
  --cert-file=/etc/etcd/ssl/etcd.pem \\
  --key-file=/etc/etcd/ssl/etcd-key.pem \\
  --peer-cert-file=/etc/etcd/ssl/etcd.pem \\
  --peer-key-file=/etc/etcd/ssl/etcd-key.pem \\
  --trusted-ca-file=/etc/etcd/ssl/ca.pem \\
  --peer-trusted-ca-file=/etc/etcd/ssl/ca.pem \\
  --initial-advertise-peer-urls=https://${NODE_IP}:2380 \\
  --listen-peer-urls=https://${NODE_IP}:2380 \\
  --listen-client-urls=https://${NODE_IP}:2379,http://127.0.0.1:2379 \\
  --advertise-client-urls=https://${NODE_IP}:2379 \\
  --initial-cluster-token=etcd-cluster-0 \\
  --initial-cluster=${ETCD_NODES} \\
  --initial-cluster-state=new \\
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

#注意，上方的环境变量一定要先配置好再进行这一步操作，在master2上export环境变量时注意修改ip
mv etcd.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable etcd
systemctl start etcd
systemctl status etcd

master2同样方法安装etcd

验证服务

etcdctl \
  --endpoints=https://${NODE_IP}:2379  \
  --ca-file=/etc/etcd/ssl/ca.pem \
  --cert-file=/etc/etcd/ssl/etcd.pem \
  --key-file=/etc/etcd/ssl/etcd-key.pem \
  cluster-health

预期结果：

2018-04-06 20:07:41.355496 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
2018-04-06 20:07:41.357436 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
member 57d56677d6df8a53 is healthy: got healthy result from https://192.168.0.170:2379
member 7ba40ace706232da is healthy: got healthy result from https://192.168.0.171:2379

若有失败，重新配置

systemctl stop etcd

rm -Rf /var/lib/etcd

rm -Rf /var/lib/etcd-cluster

mkdir -p /var/lib/etcd

systemctl start etcd

五.docker安装

若原来已经安装docker版本，建议卸载后安装docker-ce版本：

yum -y remove docker docker-common

基于aliyun安装docker-ce方法：

sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# Step 2: 添加软件源信息
sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

# Step 3: 更新并安装 Docker-CE
sudo yum makecache fast

#查看repo中所有版本的docker-ce
yum list docker-ce --showduplicates | sort -r
docker-ce.x86_64            18.03.1.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            18.03.0.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.12.1.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.12.0.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.09.1.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.09.0.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.06.2.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.06.1.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.06.0.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.03.2.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.03.1.ce-1.el7.centos             docker-ce-stable
docker-ce.x86_64            17.03.0.ce-1.el7.centos             docker-ce-stable

sudo yum -y install docker-ce-17.03.2.ce
#若提示依赖docker-ce-selinux，则先执行yum -y install  docker-ce-selinux-17.03.2.ce
# Step 4: 开启Docker服务
sudo service docker start && systemctl enbale docker 

六.安装kubelet、kubectl、kubeadm、kubecni

准备好提前下载好的rpm包：

[root@170 pkgs]# cd /root/k8s_images/pkgs
[root@170 pkgs]# ls
etcd-v3.1.10-linux-amd64.tar.gz  kubeadm-1.9.0-0.x86_64.rpm  kubectl-1.9.0-0.x86_64.rpm  kubelet-1.9.9-9.x86_64.rpm  kubernetes-cni-0.6.0-0.x86_64.rpm  socat-1.7.3.2-2.el7.x86_64.rpm

[root@170 pkgs]# yum -y install *.rpm

修改kubelet启动参数里的cgroup驱动以便兼容docker：

vi /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
#Environment="KUBELET_CGROUP_ARGS=--cgroup-driver=systemd"
Environment="KUBELET_CGROUP_ARGS=--cgroup-driver=cgroupfs"

systemctl enable docker && systemctl restart docker
systemctl daemon-reload && systemctl restart kubelet

在master2上同样操作

七.kubeadm初始化

将准备好的本地的docker images镜像导入本地仓库内

[root@170 docker_images]# ls
etcd-amd64_v3.1.10.tar    k8s-dns-dnsmasq-nanny-amd64_v1.14.7.tar  k8s-dns-sidecar-amd64_1.14.7.tar  kube-controller-manager-amd64_v1.9.0.tar  kubernetes-dashboard_v1.8.1.tar  pause-amd64_3.0.tar
flannel:v0.9.1-amd64.tar  k8s-dns-kube-dns-amd64_1.14.7.tar        kube-apiserver-amd64_v1.9.0.tar   kube-proxy-amd64_v1.9.0.tar               kube-scheduler-amd64_v1.9.0.tar


[root@170 docker_images]# for i in `ls`;do docker load -i $i;done

config.yaml初始化配置文件：

cat <<EOF > config.yaml 
apiVersion: kubeadm.k8s.io/v1alpha1
kind: MasterConfiguration
etcd:
  endpoints:
  - https://192.168.0.170:2379
  - https://192.168.0.171:2379
  
  caFile: /etc/etcd/ssl/ca.pem 
  certFile: /etc/etcd/ssl/etcd.pem 
  keyFile: /etc/etcd/ssl/etcd-key.pem
  dataDir: /var/lib/etcd
networking:
  podSubnet: 10.244.0.0/16
kubernetesVersion: 1.9.0
api:
  advertiseAddress: "192.168.0.170"
token: "b99a00.a144ef80536d4344"
tokenTTL: "0s"
apiServerCertSANs:
- "170"
- "171"
- 192.168.0.169
- 192.168.0.170
- 192.168.0.171
featureGates:
  CoreDNS: true
EOF

初始化集群

kubeadm init --config config.yaml

结果：

To start using your cluster, you need to run the following as a regular user:

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config
as root:

  kubeadm join --token b99a00.a144ef80536d4344 192.168.0.169:6443 --discovery-token-ca-cert-hash sha256:ebc2f64e9bcb14639f26db90288b988c90efc43828829c557b6b66bbe6d68dfa
  
[root@170 docker_images]# kubectl get nodes -o wide
NAME      STATUS    ROLES     AGE       VERSION   EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION          CONTAINER-RUNTIME
170       Ready     master    5h        v1.9.0    <none>        CentOS Linux 7 (Core)   3.10.0-693.el7.x86_64   docker://18.3.0
171       Ready     master    4h        v1.9.0    <none>        CentOS Linux 7 (Core)   3.10.0-693.el7.x86_64   docker://18.3.0

注意：提示信息中的kubeadm join那一行请保存好，后期使用kubeadm扩增集群node时，需要在新的node上使用这行命令加入集群

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

配置master2：

#拷贝pki 证书
mkdir -p /etc/kubernetes/pki
scp -r /etc/kubernetes/pki/ root@192.168.0.171:/etc/kubernetes/ 

#拷贝初始化配置
scp config.yaml root@192.168.0.171:/etc/kubernetes/

#在master2上初始化
kubeadm init --config /etc/kubernetes/config.yaml 

八、安装网络插件kube-router

# kube-router的daemonSet部署yaml文件地址:
# https://github.com/cloudnativelabs/kube-router/blob/master/daemonset/kubeadm-kuberouter.yaml
kubectl apply -f kubeadm-kuberouter.yaml

[root@170 docker_images]# kubectl get pods --all-namespaces
NAMESPACE     NAME                          READY     STATUS    RESTARTS   AGE
kube-system   coredns-546545bc84-j5mds      1/1       Running   2          5h
kube-system   kube-apiserver-170            1/1       Running   2          5h
kube-system   kube-apiserver-171            1/1       Running   2          4h
kube-system   kube-controller-manager-170   1/1       Running   2          5h
kube-system   kube-controller-manager-171   1/1       Running   2          4h
kube-system   kube-proxy-5dg4j              1/1       Running   2          4h
kube-system   kube-proxy-s6jtn              1/1       Running   2          5h
kube-system   kube-router-wbxvq             1/1       Running   2          4h
kube-system   kube-router-xrkbw             1/1       Running   2          4h
kube-system   kube-scheduler-170            1/1       Running   2          5h
kube-system   kube-scheduler-171            1/1       Running   2          4h

部署完成

默认情况下，为了保证master的稳定，master存在调度污点不会调度pod。取消master调度污点：

kubectl taint nodes --all node-role.kubernetes.io/master-

配置私有docker仓库，加速使用：

vim /lib/systemd/system/docker.service 
注释#ExecStart=/usr/bin/dockerd

ExecStart=/usr/bin/dockerd --insecure-registry registry.yourself.com:5000
#填写自己的docker仓库地址

---

6.8补充：
k8s集群通过kubeadm加入新的node：

在集群初始化完成时，会提示如下信息：

To start using your cluster, you need to run the following as a regular user:

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config
as root:

  kubeadm join --token b99a00.a144ef80536d4344 192.168.0.169:6443 --discovery-token-ca-cert-hash sha256:ebc2f64e9bcb14639f26db90288b988c90efc43828829c557b6b66bbe6d68dfa

其中kubeadm join是为后期新的node加入集群时使用的，在公司生产上的集群部署好时此命令没有保存，且token时有实效性的。后期有node加入集群，join命令的两个参数可以在master节点上通过如下命令获取：

token：

root@yksp009027:~# kubeadm token list
TOKEN                     TTL         EXPIRES   USAGES                   DESCRIPTION                                                EXTRA GROUPS
b97h00.a144ef08526d4345   <forever>   <never>   authentication,signing   The default bootstrap token generated by 'kubeadm init'.   system:bootstrappers:kubeadm:default-node-token

hash:

openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'
7eb62962040916673ab58b0c40fb451caef7538452f5e6c8ff7719a81fdbf633

然后在新node上执行：

kubeadm join --token=$TOKEN $MASTER_IP:6443 --discovery-token-ca-cert-hash sha256:$HASH

查看node，kubectl get nodes新node已进入Ready状态。（在join前请保证node上安装好kubelet、docker、kubeadm、kubernetes-cni、socat，并启动kubelet、docker，参考上方步骤）