Kubernetes(k8s)集群安装

一：简介

二：基础环境安装

1.系统环境

os	Role	ip	Memory
Centos 7	master01	192.168.25.30	4G
Centos 7	node01	192.168.25.31	4G
Centos 7	node02	192.168.25.31	4G

2.关闭selinux

sed -i "s/SELINUX\=.*/SELINUX=disabled/g" /etc/selinux/config

3.关闭防火墙

systemctl disable firewalld && systemctl stop firewalld

4.修改主机名

hostnamectl set-hostname Role_name

5.添加hosts解析

echo -e "192.168.25.30 master01\n192.168.25.31 node01\n192.168.25.32 node02" >> /etc/hosts

6.设置k8s内核参数

设置内核参数

cat << EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
vm.swappiness=0
EOF

加载内核模块

modprobe br_netfilter
echo "modprobe br_netfilter" >> /etc/rc.local

使内核参数生效

sysctl -p /etc/sysctl.d/k8s.conf

7.关闭系统swap

 swapoff -a

修改fstab文件，关闭swap的自动挂载。

8.修改防火墙策略

/sbin/iptables -P FORWARD ACCEPT
echo  "sleep 60 && /sbin/iptables -P FORWARD ACCEPT" >> /etc/rc.local

9.安装依赖包

yum install -y epel-release
yum install -y yum-utils device-mapper-persistent-data lvm2 net-tools conntrack-tools wget

10.时间同步

yum -y install ntpdate
/usr/sbin/ntpdate -u ntpserver1: ntp1.aliyun.com
/usr/sbin/ntpdate -u ntp1.aliyun.com

11.安装docker-ce软件

提示：master节点不需要安装

1. 删除自带的docker

   yum remove docker \
                     docker-client \
                     docker-client-latest \
                     docker-common \
                     docker-latest \
                     docker-latest-logrotate \
                     docker-logrotate \
                     docker-selinux \
                     docker-engine-selinux \
                     docker-engine
   

2. 安装依赖包

   yum install -y yum-utils \
     device-mapper-persistent-data \
     lvm2
   

3. 安装yum源

   yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
   

4. 安装docker-ce

   yum -y install docker-ce
   

5. 启动，并设置开机自启[安装设置好flanneld后，再启动docker]

   systemctl start docker && systemctl enable docker
   

11.安装CFSSL

cfssl

export CFSSL_URL="https://pkg.cfssl.org/R1.2"
wget "${CFSSL_URL}/cfssl_linux-amd64" -O /usr/local/bin/cfssl
wget "${CFSSL_URL}/cfssljson_linux-amd64" -O /usr/local/bin/cfssljson
chmod +x /usr/local/bin/cfssl /usr/local/bin/cfssljson

三：创建CA证书和密钥

​ kubernetes系统各组件需要使用TLS证书对通信进行加密，本本档使用CloudFlare的工具集cfssl来生成Certificate Authority(CA)证书和密钥文件，CA是自签名的证书，用来签名后续创建的其他TLS证书。

​ 以下操作都在master节点上执行，证书只需要创建一次即可，以后新增节点时，只需要将/etc/kubernetes/目录下的证书拷贝到新节点即可。

1.创建CA配置文件

mkdir /root/ssl
cd /root/ssl

cat > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "8760h"
    },
    "profiles": {
      "kubernetes": {
        "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ],
        "expiry": "8760h"
      }
    }
  }
}
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，后续在签名证书时会使用到某个profile；
• signing：表示该证书可用于签名其他证书；生成ca.pem证书中的CA=TRUE；
• server auto：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

2.创建CA证书签名请求

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)；浏览器检验该字段验证网站是否合法；
• “O”：Organization，kube-apiserver从证书提取该字段作为请求用户所属的组（Group）；

3.生成CA证书和私钥

# cfssl gencert -initca ca-csr.json | cfssljson -bare ca
2018/03/29 14:38:31 [INFO] generating a new CA key and certificate from CSR
2018/03/29 14:38:31 [INFO] generate received request
2018/03/29 14:38:31 [INFO] received CSR
2018/03/29 14:38:31 [INFO] generating key: rsa-2048
2018/03/29 14:38:31 [INFO] encoded CSR
2018/03/29 14:38:31 [INFO] signed certificate with serial number 438768005817886692243142700194592359153651905696

4.创建kubernetes证书签名请求文件

cat > kubernetes-csr.json << EOF
{
   "CN": "kubernetes",
    "hosts": [
      "127.0.0.1",
      "192.168.25.30",
      "192.168.25.31",
      "192.168.25.32",
      "10.254.0.1",
      "kubernetes",
      "kubernetes.default",
      "kubernetes.default.svc",
      "kubernetes.default.svc.cluster",
      "kubernetes.default.svc.cluster.local"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "ST": "BeiJing",
            "L": "BeiJing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

• hosts中的内容可以为空，即是按照上面的配置，向集群中增加新节点也不需要重新生成证书；如果hosts不为空，则需要指定授权使用该证书的IP或域名列表，由于该证书后续被etcd集群和kubernetes master集群使用，所以上面分别指定了etcd集群，kubernetes master集群的主机IP和kuberunetes服务ip。

5.生成kubernetes证书和私钥

# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kubernetes-csr.json | cfssljson -bare kubernetes
2018/03/29 14:46:12 [INFO] generate received request
2018/03/29 14:46:12 [INFO] received CSR
2018/03/29 14:46:12 [INFO] generating key: rsa-2048
2018/03/29 14:46:12 [INFO] encoded CSR
2018/03/29 14:46:12 [INFO] signed certificate with serial number 6955479006214073693226115919937339031303355422
2018/03/29 14:46:12 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for
websites. For more information see the Baseline Requirements for the Issuance and Management
of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org);
specifically, section 10.2.3 ("Information Requirements").

# ls kubernetes*
kubernetes.csr  kubernetes-csr.json  kubernetes-key.pem  kubernetes.pem

6.创建admin证书签名请求文件

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

• kube-apiserver使用RBAC对客户端（如Kubelet,kube-proxy,Pod）请求进行授权。
• kube-apiserver预定义了一些RBAC使用的RoleBindings，如cluster-admin将Group System：masters与Role cluster-admin绑定，该Role授予kube-apiserver的所有API的权限；
• OU指定该证书的Group为system:masters，kubelet使用该证书访问kube-apiserver时，由于证书为CA签名，所以认证通过，同时由于证书用户组为经过预授权的system：masters，所以被授予访问所有API的权限

7.生成admin证书和私钥

# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes admin-csr.json | cfssljson -bare admin
2018/03/29 14:57:01 [INFO] generate received request
2018/03/29 14:57:01 [INFO] received CSR
2018/03/29 14:57:01 [INFO] generating key: rsa-2048
2018/03/29 14:57:02 [INFO] encoded CSR
2018/03/29 14:57:02 [INFO] signed certificate with serial number 356467939883849041935828635530693821955945645537
2018/03/29 14:57:02 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for
websites. For more information see the Baseline Requirements for the Issuance and Management
of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org);
specifically, section 10.2.3 ("Information Requirements")

# ls admin*
admin.csr  admin-csr.json  admin-key.pem  admin.pem

8.创建kube-proxy证书签名请求文件

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

• CN指定该证书的User为system：kube-proxy；
• kube-apiserver预定义的RoleBinding cluster-admin将User system：kube-proxy与Role System：node-proxies绑定，该Role授予了调用kube-apiserver Proxy相关API的权限；

9.生成kube-proxy客户端证书和私钥

# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes  kube-proxy-csr.json | cfssljson -bare kube-proxy
2018/03/29 15:09:36 [INFO] generate received request
2018/03/29 15:09:36 [INFO] received CSR
2018/03/29 15:09:36 [INFO] generating key: rsa-2048
2018/03/29 15:09:36 [INFO] encoded CSR
2018/03/29 15:09:36 [INFO] signed certificate with serial number 225974417080991591210780916866547658424323006961
2018/03/29 15:09:36 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for
websites. For more information see the Baseline Requirements for the Issuance and Management
of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org);
specifically, section 10.2.3 ("Information Requirements").

# ls kube-proxy*
kube-proxy.csr  kube-proxy-csr.json  kube-proxy-key.pem  kube-proxy.pem

10.证书分发

将生成的证书和密钥文件（后缀为pem）拷贝到所有机器的/etc/kubernetes/ssl目录下

mkdir -p /etc/kubernetes/ssl
cp *.pem /etc/kubernetes/ssl

ssh node01 "mkdir -p /etc/kubernetes/ssl"
scp *.pem node01:/etc/kubernetes/ssl

ssh node02 "mkdir -p /etc/kubernetes/ssl"
scp *.pem node02:/etc/kubernetes/ssl

四：部署Etcd集群

​ 在三个节点都需要安装etcd，下面的操作在每台机器上操作一遍。

1.下载etcd安装包并生成命令

wget https://github.com/coreos/etcd/releases/download/v3.2.12/etcd-v3.2.12-linux-amd64.tar.gz
tar -xvf etcd-v3.2.12-linux-amd64.tar.gz
mv etcd-v3.2.12-linux-amd64/etcd* /usr/local/bin

# 生成以下两条命令
# etcd
etcd     etcdctl

2.创建工作目录

mkdir -p /var/lib/etcd

3.创建系统服务文件

master01

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 master01 \\
  --cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --peer-cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --peer-key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --peer-trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --initial-advertise-peer-urls https://192.168.25.30:2380 \\
  --listen-peer-urls https://192.168.25.30:2380 \\
  --listen-client-urls https://192.168.25.30:2379,http://127.0.0.1:2379 \\
  --advertise-client-urls https://192.168.25.30:2379 \\
  --initial-cluster-token etcd-cluster-0 \\
  --initial-cluster master01=https://192.168.25.30:2380,node01=https://192.168.25.31:2380,node02=https://192.168.25.32:2380 \\
  --initial-cluster-state new \\
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

node01

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 node01 \\
  --cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --peer-cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --peer-key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --peer-trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --initial-advertise-peer-urls https://192.168.25.31:2380 \\
  --listen-peer-urls https://192.168.25.31:2380 \\
  --listen-client-urls https://192.168.25.31:2379,http://127.0.0.1:2379 \\
  --advertise-client-urls https://192.168.25.31:2379 \\
  --initial-cluster-token etcd-cluster-0 \\
  --initial-cluster master01=https://192.168.25.30:2380,node01=https://192.168.25.31:2380,node02=https://192.168.25.32:2380 \\
  --initial-cluster-state new \\
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

node02

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 node02 \\
  --cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --peer-cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --peer-key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --peer-trusted-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --initial-advertise-peer-urls https://192.168.25.32:2380 \\
  --listen-peer-urls https://192.168.25.32:2380 \\
  --listen-client-urls https://192.168.25.32:2379,http://127.0.0.1:2379 \\
  --advertise-client-urls https://192.168.25.32:2379 \\
  --initial-cluster-token etcd-cluster-0 \\
  --initial-cluster master01=https://192.168.25.30:2380,node01=https://192.168.25.31:2380,node02=https://192.168.25.32:2380 \\
  --initial-cluster-state new \\
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

• 指定etcd的工作目录为/var/lib/etcd，数据目录为/var/lib/etcd，需在启动服务前创建这个目录，否则启动服务的时候会报错“Failed at step CHDIR spawning /usr/bin/etcd: No such file or directory”；
• 为了保证通信安全，需要指定etcd的公私钥(cert-file和key-file),Peers通信的公私钥和CA 证书(peer-cert-file、peer-key-file、peer-trusted-ca-file)、客户端的CA证书（trusted-ca-file）；
• 创建kubernetes.pem证书时使用的kubernestes-csr.json文件的hosts字段包含所有的etcd节点的IP，否则证书校验会出错；
• --initial-cluster-state值为new时，-name的参数值必须位于-initial-cluster列表中；

4.启动etcd服务

cp etcd.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable etcd
systemctl start etcd
systemctl status etcd

5.验证etcd服务

# etcdctl \
    --ca-file=/etc/kubernetes/ssl/ca.pem \
    --cert-file=/etc/kubernetes/ssl/kubernetes.pem \
    --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
    cluster-health
member 2ea4d6efe7f32da is healthy: got healthy result from https://192.168.25.32:2379
member 5246473f59267039 is healthy: got healthy result from https://192.168.25.31:2379
member be723b813b44392b is healthy: got healthy result from https://192.168.25.30:2379
cluster is healthy

五：部署Flannel

在node节点上都需要部署安装

1.下载安装Flannel

wget https://github.com/coreos/flannel/releases/download/v0.9.1/flannel-v0.9.1-linux-amd64.tar.gz
mkdir flannel
tar -xzvf flannel-v0.9.1-linux-amd64.tar.gz -C flannel
cp flannel/{flanneld,mk-docker-opts.sh} /usr/local/bin

2.向etcd中写入网段信息，只需要在一台执行即可

etcdctl --endpoints=https://192.168.25.30:2379,https://192.168.25.31:2379,https://192.168.25.32:2379 \
  --ca-file=/etc/kubernetes/ssl/ca.pem \
  --cert-file=/etc/kubernetes/ssl/kubernetes.pem \
  --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
  mkdir /kubernetes/network

etcdctl --endpoints=https://192.168.25.30:2379,https://192.168.25.31:2379,https://192.168.25.32:2379 \
  --ca-file=/etc/kubernetes/ssl/ca.pem \
  --cert-file=/etc/kubernetes/ssl/kubernetes.pem \
  --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
  mk /kubernetes/network/config '{"Network":"172.30.0.0/16","SubnetLen":24,"Backend":{"Type":"vxlan"}}'

3.创建服务启动文件

cat > flanneld.service << EOF
[Unit]
Description=Flanneld overlay address etcd agent
After=network.target
After=network-online.target
Wants=network-online.target
After=etcd.service
Before=docker.service

[Service]
Type=notify
ExecStart=/usr/local/bin/flanneld \\
  -etcd-cafile=/etc/kubernetes/ssl/ca.pem \\
  -etcd-certfile=/etc/kubernetes/ssl/kubernetes.pem \\
  -etcd-keyfile=/etc/kubernetes/ssl/kubernetes-key.pem \\
  -etcd-endpoints=https://192.168.25.30:2379,https://192.168.25.31:2379,https://192.168.25.32:2379 \\
  -etcd-prefix=/kubernetes/network
ExecStartPost=/usr/local/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/docker
Restart=on-failure

[Install]
WantedBy=multi-user.target
RequiredBy=docker.service
EOF

• mk-docker-opts.sh：将分配给flanneld的pod子网网段信息写入到/run/flannel/docker文件中，后续docker启动时使用这个文件中参数值设置docker0网桥
• flanneld使用系统缺省路由所在的接口和其他节点通信，对于有多个网络接口的机器（如内网和公网），可使用-iface=enpxx选项值指定通信接口；

4.启动Flanneld服务

mv flanneld.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable flanneld
systemctl start flanneld
systemctl status flanneld

5.检查flanneld服务状态

# /usr/local/bin/etcdctl \
 --endpoints=https://192.168.25.30:2379,https://192.168.25.31:2379,https://192.168.25.32:2379 \
 --ca-file=/etc/kubernetes/ssl/ca.pem \
 --cert-file=/etc/kubernetes/ssl/kubernetes.pem \
 --key-file=/etc/kubernetes/ssl/kubernetes-key.pem \
 ls /kubernetes/network/subnets
 /kubernetes/network/subnets/172.30.82.0-24
/kubernetes/network/subnets/172.30.1.0-24
/kubernetes/network/subnets/172.30.73.0-24

6.配置docker使用flanneld网络

/usr/lib/systemd/system/docker.service

[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target

[Service]
Type=notify
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
# 修改
ExecStart=/usr/bin/dockerd $DOCKER_NETWORK_OPTIONS
# 新增
EnvironmentFile=/run/flannel/docker

ExecReload=/bin/kill -s HUP $MAINPID
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
# Uncomment TasksMax if your systemd version supports it.
# Only systemd 226 and above support this version.
#TasksMax=infinity
TimeoutStartSec=0
# set delegate yes so that systemd does not reset the cgroups of docker containers
Delegate=yes
# kill only the docker process, not all processes in the cgroup
KillMode=process
# restart the docker process if it exits prematurely
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s

[Install]
WantedBy=multi-user.target

• flanneld 启动时将网络配置写入到 /run/flannel/docker 文件中的变量 DOCKER_NETWORK_OPTIONS，dockerd 命令行上指定该变量值来设置 docker0 网桥参数；
• 如果指定了多个 EnvironmentFile 选项，则必须将 /run/flannel/docker 放在最后(确保 docker0 使用 flanneld 生成的 bip 参数)；
• 不能关闭默认开启的 –iptables 和 –ip-masq 选项；
• 如果内核版本比较新，建议使用 overlay 存储驱动；
• –exec-opt native.cgroupdriver=systemd参数可以指定为”cgroupfs”或者“systemd”

7.启动docker

systemctl daemon-reload && systemctl start docker && systemctl enable docker

六：部署kubectl工具

​ kubectl是kubernetes的集群管理工具，任何节点通过kubetcl都可以管理整个k8s集群。本文档部署在master01这个节点，部署成功后会生成/root/.kube/config文件，kubectl就是通过这个获取kube-apiserver地址，证书，用户名等信息。

1.下载安装包

wget https://dl.k8s.io/v1.8.6/kubernetes-client-linux-amd64.tar.gz
tar -xzvf kubernetes-client-linux-amd64.tar.gz
sudo cp kubernetes/client/bin/kube* /usr/local/bin/
chmod a+x /usr/local/bin/kube*
export PATH=/root/local/bin:$PATH

2.创建/root/.kube/config文件

# 设置集群参数,--server指定Master节点ip
kubectl config set-cluster kubernetes \
  --certificate-authority=/etc/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=https://192.168.25.30:6443

# 设置客户端认证参数
kubectl config set-credentials admin \
  --client-certificate=/etc/kubernetes/ssl/admin.pem \
  --embed-certs=true \
  --client-key=/etc/kubernetes/ssl/admin-key.pem

# 设置上下文参数
kubectl config set-context kubernetes \
  --cluster=kubernetes \
  --user=admin

# 设置默认上下文
kubectl config use-context kubernetes

• admin.pem：证书O字段值为system:masters，kube-apiserver预定义的RoleBinding cluster-admin将Group system:master与Role cluster-admin绑定，该Role 授予了调用Kube-apiserver相关的API权限

3.创建bootstartp.kubeconfig文件

#生成token 变量
export BOOTSTRAP_TOKEN=$(head -c 16 /dev/urandom | od -An -t x | tr -d ' ')

cat > token.csv <<EOF
${BOOTSTRAP_TOKEN},kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF

mv token.csv /etc/kubernetes/

# 设置集群参数--server为master节点ip
kubectl config set-cluster kubernetes \
  --certificate-authority=/etc/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=https://192.168.25.30:6443 \
  --kubeconfig=bootstrap.kubeconfig

# 设置客户端认证参数
kubectl config set-credentials kubelet-bootstrap \
  --token=${BOOTSTRAP_TOKEN} \
  --kubeconfig=bootstrap.kubeconfig

# 设置上下文参数
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kubelet-bootstrap \
  --kubeconfig=bootstrap.kubeconfig

# 设置默认上下文
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

mv bootstrap.kubeconfig /etc/kubernetes/

4.创建kube-proxy.kubeconfig

# 设置集群参数 --server参数为master ip
kubectl config set-cluster kubernetes \
  --certificate-authority=/etc/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=https://192.168.25.30:6443 \
  --kubeconfig=kube-proxy.kubeconfig

# 设置客户端认证参数
kubectl config set-credentials kube-proxy \
  --client-certificate=/etc/kubernetes/ssl/kube-proxy.pem \
  --client-key=/etc/kubernetes/ssl/kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig

# 设置上下文参数
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig

# 设置默认上下文
kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
mv kube-proxy.kubeconfig /etc/kubernetes/

• 设置集群参数和客户端认证参数，--embed-certs都为true，这会将certificate-authority，client-cretificate和client-key指向的证书文件内容写入到生成的kube-proxy.kebuconfig文件中；
• kube-proxy.pem证书中CN为system:kube-proxy,kube-apiserver预定义的RoleBinding cluster-admin将User system:kube-proxy与Role system:node-proxy绑定，该Role授予了调用kube-apiserver Proxy相关的api权限；

5.将生成的配置文件拷贝到其他的节点

scp /etc/kubernetes/kube-proxy.kubeconfig node01:/etc/kubernetes/
scp /etc/kubernetes/kube-proxy.kubeconfig node02:/etc/kubernetes/

scp /etc/kubernetes/bootstrap.kubeconfig node01:/etc/kubernetes/
scp /etc/kubernetes/bootstrap.kubeconfig node02:/etc/kubernetes/

七：部署master节点

1.下载安装文件

wget https://dl.k8s.io/v1.8.6/kubernetes-server-linux-amd64.tar.gz
tar -xzvf kubernetes-server-linux-amd64.tar.gz
cp -r kubernetes/server/bin/{kube-apiserver,kube-controller-manager,kube-scheduler,kubectl,kube-proxy,kubelet} /usr/local/bin/

2.部署apiserver服务

配置kube-apiserver服务管理文件

cat > kube-apiserver.service << EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=network.target
After=etcd.service

[Service]
ExecStart=/usr/local/bin/kube-apiserver \\
  --logtostderr=true \\
  --admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,ResourceQuota,NodeRestriction \\
  --advertise-address=192.168.25.30 \\
  --bind-address=192.168.25.30 \\
  --insecure-bind-address=127.0.0.1 \\
  --authorization-mode=Node,RBAC \\
  --runtime-config=rbac.authorization.k8s.io/v1alpha1 \\
  --kubelet-https=true \\
  --enable-bootstrap-token-auth \\
  --token-auth-file=/etc/kubernetes/token.csv \\
  --service-cluster-ip-range=10.254.0.0/16 \\
  --service-node-port-range=8400-10000 \\
  --tls-cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
  --tls-private-key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --client-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --service-account-key-file=/etc/kubernetes/ssl/ca-key.pem \\
  --etcd-cafile=/etc/kubernetes/ssl/ca.pem \\
  --etcd-certfile=/etc/kubernetes/ssl/kubernetes.pem \\
  --etcd-keyfile=/etc/kubernetes/ssl/kubernetes-key.pem \\
  --etcd-servers=https://192.168.25.30:2379,https://192.168.25.31:2379,https://192.168.25.32:2379 \\
  --enable-swagger-ui=true \\
  --allow-privileged=true \\
  --apiserver-count=3 \\
  --audit-log-maxage=30 \\
  --audit-log-maxbackup=3 \\
  --audit-log-maxsize=100 \\
  --audit-log-path=/var/lib/audit.log \\
  --event-ttl=1h \\
  --v=2
Restart=on-failure
RestartSec=5
Type=notify
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

• --authorization-mode=RBAC 指定在安全端口使用RBAC模式，拒绝未通过授权的请求；
• kube-scheduler，kube-controller-manager一般和kube-apiserver部署在同一台机器上，他们使用非安全端口和kube-apiserver通信；
• kubelet，kube-proxy，kubectl部署在其他Node节点，如果通过安全端口访问kube-apiserver，则必须先通过TLS证书认证，再通过RBAC授权；
• kube-proxy，kubectl通过在使用的证书里指定相关的User，Group来达到通过RBAC授权的目的。
• Bootstartp：如果使用了kubelet TLS Bootstartp机制，则不能再指定 –kubelet-certificate-authority、–kubelet-client-certificate 和 –kubelet-client-key 选项，否则后续kube-apiserver校验kubelet证书时出现”x509: certificate signed by unknown authority“ 错误；
• --admission-control值必须包含ServiceAccount，否则部署集群插件时会失败；
• --bind-address不能为127.0.0.1；
• --runtime-config：配置rbac.authorization.k8s.io/v1beta1，表示运行时的apiVersion；
• service-cluster-ip-range：指定Service cluster ip段地址，该地址路由不可达；
• --service-node-port-range：指定NodePort的端口范围

确实情况下，kubernetes对像保存在etcd的/registry路径下，可以通过--etcd-prefix参数进行跳转

启动服务，并设置开启自启

cp kube-apiserver.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable kube-apiserver
systemctl start kube-apiserver
systemctl status kube-apiserver

3.部署manager服务

生成服务启动脚本

cat > kube-controller-manager.service << EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
ExecStart=/usr/local/bin/kube-controller-manager \\
  --logtostderr=true  \\
  --address=127.0.0.1 \\
  --master=http://127.0.0.1:8080 \\
  --allocate-node-cidrs=true \\
  --service-cluster-ip-range=10.254.0.0/16 \\
  --cluster-cidr=172.30.0.0/16 \\
  --cluster-name=kubernetes \\
  --cluster-signing-cert-file=/etc/kubernetes/ssl/ca.pem \\
  --cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem \\
  --service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem \\
  --root-ca-file=/etc/kubernetes/ssl/ca.pem \\
  --leader-elect=true \\
  --v=2
Restart=on-failure
LimitNOFILE=65536
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

• --address的值必须为127.0.0.1,应为当前kube-apiserver期望scheduler和conntroller-manaager在同一台机器上；
• --master=http://{master_ip}:8080：使用非安全的8080端口与kube-apiserver通信；
• --cluster-cidr指定Cluster中Pod的CIDR范围，该网段在各Node必须路由可达（flanneld保证）
• --service-cluster-ip-range参数指定Cluster中Service的CIDR范围，该网络在各Node间必须路由不可达，必须与kube-apiserver中的参数保持一致；
• --cluster-signing-*指定的证书和私钥文件用来签名TLS BootStrap创建的证书和私钥
• --root-ca-file用来对kube-apiserver证书进行校验，指定该参数后，才会在Pod容器的ServiceAccount中放置该CA证书文件
• --leader-elect=true部署多台master集群时选举产生一直处于工作状态的kube-controller-manager进程；

启动服务

cp kube-controller-manager.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable kube-controller-manager
systemctl start kube-controller-manager
systemctl status kube-controller-manage

4.部署scheduler服务

配置kube-scheduler

cat > kube-scheduler.service << EOF
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
ExecStart=/usr/local/bin/kube-scheduler \\
  --logtostderr=true \\
  --address=127.0.0.1 \\
  --master=http://127.0.0.1:8080 \\
  --leader-elect=true \\
  --v=2
Restart=on-failure
LimitNOFILE=65536
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

• --address必须为127.0.0.1，应为当前kube-apiserver期望scheduler和contorller-manager在同一主机；
• master=http://{MASTER_IP}:8080：使用非安全 8080 端口与 kube-apiserver 通信；
• –leader-elect=true 部署多台机器组成的 master 集群时选举产生一处于工作状态的 kube-controller-manager 进程；

启动kube-scheduler

cp kube-scheduler.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable kube-scheduler
systemctl start kube-scheduler
systemctl status kube-scheduler

5.验证master节点

# kubectl get componentstatuses
NAME                 STATUS    MESSAGE              ERROR
scheduler            Healthy   ok
controller-manager   Healthy   ok
etcd-2               Healthy   {"health": "true"}
etcd-1               Healthy   {"health": "true"}
etcd-0               Healthy   {"health": "true"}

八:部署Node节点

1.部署kubelet服务

​ kubelet在启动时向kube-apiserver发送TLS bootstrapping请求，需要先将bootstrap token文件中的kubelet-bootstrap用户赋予system:node-bootstrapper角色，然后kubelet才有权限创建认证请求。

授权,在master上运行一次即可

kubectl create clusterrolebinding kubelet-bootstrap --clusterrole=system:node-bootstrapper --user=kubelet-bootstrap

下载和安装kubelet和kube-proxy

wget https://dl.k8s.io/v1.8.6/kubernetes-server-linux-amd64.tar.gz
tar -xzvf kubernetes-server-linux-amd64.tar.gz
cp -r kubernetes/server/bin/{kube-proxy,kubelet} /usr/local/bin/

创建kubelet工作目录

mkdir /var/lib/kubelet

配置kubelt

master01

cat > kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=docker.service
Requires=docker.service

[Service]
WorkingDirectory=/var/lib/kubelet
ExecStart=/usr/local/bin/kubelet \\
  --address=192.168.25.30 \\
  --hostname-override=192.168.25.30 \\
  --pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest \\
  --experimental-bootstrap-kubeconfig=/etc/kubernetes/bootstrap.kubeconfig \\
  --kubeconfig=/etc/kubernetes/kubelet.kubeconfig \\
  --require-kubeconfig \\
  --cert-dir=/etc/kubernetes/ssl \\
  --container-runtime=docker \\
  --cluster-dns=10.254.0.2 \\
  --cluster-domain=cluster.local \\
  --hairpin-mode promiscuous-bridge \\
  --allow-privileged=true \\
  --serialize-image-pulls=false \\
  --register-node=true \\
  --logtostderr=true \\
  --cgroup-driver=cgroupfs  \\
  --v=2

Restart=on-failure
KillMode=process
LimitNOFILE=65536
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

• --address：本机IP，不能设置为127.0.0.1，否则后续Pods访问kubelet的API接口时会失败，因为 Pods 访问的 127.0.0.1 指向自己，而不是 kubelet;
• --hostname-overeide：本机IP；
• --cgroup-driver配置成cgroupfs（保持docker和kubelet中的cgroup driver配置一致即可）；
• --experimental-bootstrap-kubeconfig指向bootstrap kubeconfig文件，kubelet使用该文件中的用户名和token向kube-apiserver发送TLS Bootstrapping请求；
• 管理员通过了CSR请求后，kubelet自动在--cert-dir目录创建证书和私钥文件（kubelet-client.crt和kubelet-client.key）,然后写入--kubeconfig文件（自动创建）
• 建议在--kubeconfig配置文件中指定kube-apiserver地址，如果未指定--api-servers选项，则必须指定--require-kubeconfig选项后才从配置文件中读取kube-apiserver的地址，否则kubelet启动后会找不到kube-apiserver（日志中提示找不到API server），kubectl get nodes不会返回对应的Node信息；
• --cluster-dns指定kubedns的Service ip(可以先分配，后续创建kubedns服务时指定该IP)，--cluster-domain指定域名后缀，这两个参数同时配置才会生效；
• --cluster-domain指定pod启动时/etc/resolve.conf文件中的search domain，起初我们将其配置成了 cluster.local.，这样在解析 service 的 DNS 名称时是正常的，可是在解析 headless service 中的 FQDN pod name 的时候却错误，因此我们将其修改为 cluster.local，去掉嘴后面的 ”点号“ 就可以解决该问题；
• --kubeconfig=/etc/kubernetes/kubelet.kubeconfig中指定的kubelet.kubeconfig文件在第一次启动kubelet之前并不存在，请看下文，当通过CSR请求后，会自动生成，如果你的节点节点上已经生成了~/.kube/config文件，你可以将该文件拷贝到该路径面，并命名为kubelet.kubeconfig文件，所有的节点可以共用同一个config文件，这样新添加节点时就不需要再创建CSR请求就能自动添加到kubernetes集群中，同样，在任意能够访问到kubernetes集群的主机上使用kubectl --kubeconfig命令操作集群，只要使用~/.kube/config文件就能通过权限认证，应为这个文件的认证信息为admin，对集群有所有权限。

启动kubelet服务

cp kubelet.service /etc/systemd/system/kubelet.service
systemctl daemon-reload
systemctl enable kubelet
systemctl start kubelet
systemctl status kubelet

2.执行TLS证书授权请求

kubelet首次启动时像kube-apiserver发送证书签名求情，必须通过授权后，才会添加到集群。

查询授权请求

# kubectl get csr
NAME                                                   AGE       REQUESTOR           CONDITION
node-csr-450A0zCMYrGxWozsNukv6vh2NdBspA-hr6Rsz-LA9ro   3m        kubelet-bootstrap   Pending
node-csr-5t_AUkaEhT98xX1g7zTpzaNzRB9rXh453i2Fu_yxvvs   3m        kubelet-bootstrap   Pending
node-csr-p9r9gusX2kTGpyYFPlkoaSGyatLQmtDmL8NBee2D_s8   3m        kubelet-bootstrap   Pending

同意授权请求

# kubectl certificate approve node-csr-450A0zCMYrGxWozsNukv6vh2NdBspA-hr6Rsz-LA9ro
certificatesigningrequest "node-csr-450A0zCMYrGxWozsNukv6vh2NdBspA-hr6Rsz-LA9ro" approved

# kubectl certificate approve node-csr-5t_AUkaEhT98xX1g7zTpzaNzRB9rXh453i2Fu_yxvvs
certificatesigningrequest "node-csr-5t_AUkaEhT98xX1g7zTpzaNzRB9rXh453i2Fu_yxvvs" approved

# kubectl certificate approve node-csr-p9r9gusX2kTGpyYFPlkoaSGyatLQmtDmL8NBee2D_s8
certificatesigningrequest "node-csr-p9r9gusX2kTGpyYFPlkoaSGyatLQmtDmL8NBee2D_s8" approved

查看所有集群节点

# kubectl get nodes
NAME            STATUS    ROLES     AGE       VERSION
192.168.25.30   Ready     <none>    15m       v1.8.6
192.168.25.31   Ready     <none>    15m       v1.8.6
192.168.25.32   Ready     <none>    15m       v1.8.6

3.部署kube-proxy服务

创建工作目录

mkdir -p /var/lib/kube-proxy

配置kube-proxy服务

cat > kube-proxy.service << EOF
[Unit]
Description=Kubernetes Kube-Proxy Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=network.target

[Service]
WorkingDirectory=/var/lib/kube-proxy
ExecStart=/usr/local/bin/kube-proxy \\
  --bind-address=192.168.25.30 \\
  --hostname-override=192.168.25.30 \\
  --cluster-cidr=10.254.0.0/16 \\
  --kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig \\
  --logtostderr=true \\
  --v=2
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

• --bind-address：本机ip
• --hostname-override：本机ip，必须需kubelet的值一致，否则kube-proxy启动后找不到node，从而影响任何iptables规则
• --cluster-cidr：必须与kube-apiserver的--service-cluster-ip-range选项值一致，kube-proxy根据--clister-cidr判断集群内部和外部流量，指定--cluster-cidr或--masquerade-all选项后kube-proxy才会对访问service ip的请求做SNAT；
• –kubeconfig 指定的配置文件嵌入了 kube-apiserver 的地址、用户名、证书、秘钥等请求和认证信息；
• 预定义的 RoleBinding cluster-admin 将User system:kube-proxy 与 Role system:node-proxier 绑定，该 Role 授予了调用 kube-apiserver Proxy 相关 API 的权限；

启动kube-proxy服务

cp kube-proxy.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable kube-proxy
systemctl start kube-proxy
systemctl status kube-proxy

九:插件安装

由于默认镜像为谷歌镜像，所以是需要修改的，所以用docker hup做了跳转，修改好的yamk文件下载地址如下：

百度网盘(o3z9)

1.dns插件

wget https://github.com/kubernetes/kubernetes/releases/download/v1.8.6/kubernetes.tar.gz
tar xzvf kubernetes.tar.gz

cd /root/kubernetes/cluster/addons/dns
mv  kubedns-svc.yaml.sed kubedns-svc.yaml
#把文件中$DNS_SERVER_IP替换成10.254.0.2
sed -i 's/$DNS_SERVER_IP/10.254.0.2/g' ./kubedns-svc.yaml

mv ./kubedns-controller.yaml.sed ./kubedns-controller.yaml
#把$DNS_DOMAIN替换成cluster.local
sed -i 's/$DNS_DOMAIN/cluster.local/g' ./kubedns-controller.yaml

ls *.yaml
kubedns-cm.yaml  kubedns-controller.yaml  kubedns-sa.yaml  kubedns-svc.yaml

kubectl create -f .

2.dashboard插件

下载部署文件

wget https://raw.githubusercontent.com/kubernetes/dashboard/v1.8.1/src/deploy/recommended/kubernetes-dashboard.yaml

修改部署文件

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
spec:
  # 新增
  type: NodePort
  ports:
    - port: 443
      targetPort: 8443
      # 新增
      nodePort: 8510
  selector:
    k8s-app: kubernetes-dashboard

创建pod

kubectl create -f kubernetes-dashboard.yaml

部署认证服务

cat > ./kubernetes-dashboard-admin.rbac.yaml << EOF
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: dashboard-admin
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard
  namespace: kube-system
EOF

kubectl create -f kubernetes-dashboard-admin.rbac.yaml

访问地址，目前只能火狐访问

https://192.168.25.30:8510

3.heapster插件

下载安装文件

wget https://github.com/kubernetes/heapster/archive/v1.5.0.tar.gz
tar xzvf ./v1.5.0.tar.gz
cd ./heapster-1.5.0/

kubectl create -f deploy/kube-config/influxdb/
kubectl create -f deploy/kube-config/rbac/heapster-rbac.yaml123456

确认所有pod都正常启动

kubectl get pods --all-namespaces

十：常用服务部署

1.nginx

部署文件：

apiVersion: v1
kind: Pod
metadata:
  name: nginx
  labels:
     app: nginx
spec:
  containers:
     - name: nginx
       image: registry.cn-qingdao.aliyuncs.com/k8/nginx:1.9.0
       imagePullPolicy: IfNotPresent
       ports:
       - containerPort: 80
  restartPolicy: Always
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
spec:
  type: NodePort
  sessionAffinity: ClientIP
  selector:
    app: nginx
  ports:
    # 将容器的80端口映射到master主机的8888端口
    - port: 80
      nodePort: 8888

2.mysql

部署文件：

apiVersion: v1
kind: Pod
metadata:
  name: mysql
  labels:
     app: mysql
spec:
  containers:
     - name: mysql
       image: mysql
       # 环境变量
       env:
       - name: MYSQL_ROOT_PASSWORD
         value: "123456"
       imagePullPolicy: IfNotPresent
       # 容器暴露端口
       ports:
       - containerPort: 3306
  restartPolicy: Always
---
apiVersion: v1
kind: Service
metadata:
  name: mysql-service
spec:
  type: NodePort
  sessionAffinity: ClientIP
  selector:
    app: mysql
  ports:
    - port: 3306
      nodePort: 9306

十一：常用命令

1.查看kubelet log

journalctl -u kubelet -f

2.查看pods信息

kubectl get pods --all-namespaces

3.查看service信息

kubectl get pods --all-namespaces