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

摘要：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关闭防火墙启动验证集群状态晚上回去更新第二篇从零开始安装以及的配置以及作用

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。

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

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

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

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"
    }
]
}

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

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/

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/...

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

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。

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

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