【从零开始安装kubernetes-1.7.3】1.环境说明以及etcd配置（CA认证）

1.环境说明

主机名	ip	说明
master-123(复用node)	192.168.116.123	etcd flannel kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
node-124	192.168.116.124	flannel kubelet kube-proxy

由于目前只有2台机器，etcd集群由于竞选原因至少需要奇数台机器才能稳定运行，所以目前暂时使用1台机器安装etcd。

2.初始化环境（修改主机名）

192.168.116.123执行：hostnamectl --static set-hostname master-123
192.168.116.124执行：hostnamectl --static set-hostname node-124

编辑 /etc/hosts文件，配置hostname通信

vi /etc/hosts

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.116.123 master-123
192.168.116.124 node-124

3.使用cfssl创建CA证书并分发证书

3.1 安装cfssl

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

3.2 CA证书配置

配置config.json文件

{
"signing": {
    "default": {
        "expiry": "87600h"
    },
    "profiles": {
        "kubernetes": {
            "usages": [
                "signing",
                "key encipherment",
                "server auth",
                "client auth"
            ],
            "expiry": "87600h"
        }
    }
}
}

配置csr.json文件

{
"CN": "kubernetes",
"key": {
    "algo": "rsa",
    "size": 2048
},
"names": [
    {
        "C": "CN",
        "ST": "ShangHai",
        "L": "ShangHai",
        "O": "k8s",
        "OU": "System"
    }
]
}

3.3 生成CA证书以及私钥

mkdir –p /opt/ssl
cd /opt/ssl

执行：cfssl gencert -initca csr.json | cfssljson -bare ca

[root@localhost ssl]# ls -ltr
total 20
-rw-r--r--. 1 root root  387 Jul 27 15:01 config.json
-rw-r--r--. 1 root root  267 Jul 27 15:04 csr.json
-rw-r--r--. 1 root root 1363 Jul 27 15:07 ca.pem
-rw-------. 1 root root 1675 Jul 27 15:07 ca-key.pem
-rw-r--r--. 1 root root 1005 Jul 27 15:07 ca.csr

3.4 分发证书

创建证书目录

mkdir -p /etc/kubernetes/ssl

拷贝所有文件至目录下

cp * /etc/kubernetes/ssl/

将文件拷贝至所有k8s机器上

scp * root@192.168.116.124:/etc/kubernetes/ssl/

4.安装etcd并配置CA认证

etcd作为一个高可用键值存储系统，天生就是为集群化而设计的。由于Raft算法在做决策时需要多数节点的投票，所以etcd一般部署集群推荐奇数个节点，推荐的数量为3、5或者7个节点构成一个集群。

上传文件：etcd-3.1.7-1.el7.x86_64.rpm
执行命令：rpm -ivh etcd-3.1.7-1.el7.x86_64.rpm
下载地址：http://www.rpmfind.net/linux/...

4.1 安装etcd证书

现在只在单matser上创建etcd，之后etcd会添加2个节点

cd /opt/ssl
vi etcd-csr.json
{
  "CN": "etcd",
  "hosts": [
    "127.0.0.1",
    "192.168.116.123",
    "192.168.116.124",
    "192.168.116.120",
    "192.168.116.123",
    "192.168.116.124",
    "192.168.116.125",
    "192.168.116.120"
  ],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "ShangHai",
      "L": "ShangHai",
      "O": "k8s",
      "OU": "System"
    }
  ]
}

上面配置文件的ip尽量包括所有etcd节点的ip，否则需要重新分发证书
生成etcd密钥

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

查看生成

[root@localhost ssl]# ls -ltr etcd*
-rw-r--r--. 1 root root  295 Jul 27 15:22 etcd-csr.json
-rw-r--r--. 1 root root 1440 Jul 27 15:24 etcd.pem
-rw-------. 1 root root 1679 Jul 27 15:24 etcd-key.pem
-rw-r--r--. 1 root root 1066 Jul 27 15:24 etcd.csr

拷贝到etcd服务器

cp etcd* /etc/kubernetes/ssl/
scp etcd* root@198.15.5.28:/etc/kubernetes/ssl
scp etcd* root@198.15.5.29:/etc/kubernetes/ssl

如果 etcd 非 root 用户，读取证书会提示没权限
在每一台ETCD节点上运行

chmod 644 /etc/kubernetes/ssl/etcd-key.pem

4.2 配置etcd服务

vi /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/
User=etcd
# set GOMAXPROCS to number of processors
ExecStart=/usr/bin/etcd \
  --name=etcd1 \
  --cert-file=/etc/kubernetes/ssl/etcd.pem \
  --key-file=/etc/kubernetes/ssl/etcd-key.pem \
  --peer-cert-file=/etc/kubernetes/ssl/etcd.pem \
  --peer-key-file=/etc/kubernetes/ssl/etcd-key.pem \
  --trusted-ca-file=/etc/kubernetes/ssl/ca.pem \
  --peer-trusted-ca-file=/etc/kubernetes/ssl/ca.pem \
  --initial-advertise-peer-urls=https://192.168.116.123:2380 \
  --listen-peer-urls=https://192.168.116.123:2380 \
  --listen-client-urls=https://192.168.116.123:2379,http://127.0.0.1:2379 \
  --advertise-client-urls=https://192.168.116.123:2379 \
  --initial-cluster-token=k8s-etcd-cluster \
  --initial-cluster=etcd1=https://192.168.116.123:2380 \
  --initial-cluster-state=new \
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

如果是多台etcd，应根据各节点ip的不同修改ip，--initial-cluster=etcd1=https://192.168.116.123:2380应该为所有节点而不是单个节点。

4.3 所有主机关闭防火墙

关闭所有节点主机防火墙
关闭防火墙开机自启动：systemctl disable firewalld
关闭防火墙： systemctl stop firewalld

启动etcd：

systemctl daemon-reload
systemctl enable etcd
systemctl start etcd
systemctl status etcd

4.4 验证etcd集群状态

etcdctl --endpoints=https://192.168.116.123:2379 \
        --cert-file=/etc/kubernetes/ssl/etcd.pem \
        --ca-file=/etc/kubernetes/ssl/ca.pem \
        --key-file=/etc/kubernetes/ssl/etcd-key.pem \
        cluster-health

etcdctl --endpoints=https://192.168.116.123:2379 \
    --cert-file=/etc/kubernetes/ssl/etcd.pem \
    --ca-file=/etc/kubernetes/ssl/ca.pem \
    --key-file=/etc/kubernetes/ssl/etcd-key.pem \
    member list

晚上回去更新第二篇：

【从零开始安装kubernetes-1.7.3】2.flannel、docker以及Harbor的配置以及作用