etcd集群搭建

Posted baijuminglu

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主机

kubermaster1 192.168.4.11
kubermaster2 192.168.4.12
kubermaster3 192.163.4.13

系统

[[email protected] etcd-v3.2.11-linux-amd64]# cat /etc/redhat-release 
CentOS Linux release 7.4.1708 (Core)

TLS密钥和证书

这里部署的etcd集群使用TLS证书对证书通信进行加密，并开启基于CA根证书签名的双向数字证书认证。

安装go语言组件

登录 https://golang.org/dl/ 找到最新版的go并下载

cd /usr/local/src
wget http://redirector.gvt1.com/edgedl/go/go1.9.2.linux-amd64.tar.gz
tar -xvf go1.9.2.linux-amd64.tar.gz -C /usr/local

配置go环境

cat >> /etc/profile << EOF
#go的安装路径
export GOROOT=/usr/local/go
#go安装的工具路径
export GOPATH=/apps/local/go
export PATH=$GOROOT/bin:$PATH
EOF
source /etc/profile

GOPATH和GOROOT不能相同

配置生效

[[email protected] bin]# go version
go version go1.9.2 linux/amd64

安装cfssl

将会用使用cfssl生成所需要的私钥和证书

go get -u github.com/cloudflare/cfssl/cmd/...

会在$GOPATH/bin下安装cfssl, cfssjosn, mkbundle等工具。

创建CA证书和私钥，准备为etcd和其它组件办法证书和签名

创建ca-config.json

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

ca-config.json中可以定义多个profile，分别设置不同的expiry和usages等参数。如上面的ca-config.json中定义了名称为aspire的profile，这个profile的expiry 87600h为10年，useages中：

  • signing表示此CA证书可以用于签名其他证书，ca.pem中的CA=TRUE
  • server auth表示TLS Server Authentication
  • client auth表示TLS Client Authentication

创建CA证书签名请求配置ca-csr.json

{
  "CN": "aspire",
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "BeiJing",
      "L": "BeiJing",
      "O": "aspire",
      "OU": "cloudnative"
    }
  ]
}

生成CA证书和私钥

cfssl gencert -initca ca-csr.json | cfssljson -bare ca
ls
ca-config.json  ca.csr  ca-csr.json  ca-key.pem  ca.pem

生成etcd证书和私钥

创建etcd证书签名请求配置etcd-csr.json

{
    "CN": "aspire.etcd",
    "hosts": [
      "127.0.0.1",
      "192.168.4.11",
      "192.168.4.12",
      "192.168.4.13",
      "kubermaster1",
      "kubermaster2",
      "kubermaster3"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "ST": "BeiJing",
            "L": "BeiJing",
            "O": "aspire.etcd",
            "OU": "Operation and maintenance center"
        }
    ]
}

该"hosts"是可以使用该证书域名列表。‘CN’，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；

该"names"值实际上是名称对象的列表。每个名称对象应至少包含一个“C”，“L”，“O”，“OU”或“ST”值（或这些的任意组合）。这些值是：

  • “C”：国家
  • “L”：地区或城市（如城市或城镇名称）
  • “O”：组织 Organization，kube-apiserver从证书中提取该字段作为请求用户所属的组 (Group)；
  • “OU”：组织单位，如负责拥有密钥的部门; 它也可以用于“做生意”（DBS）的名称
  • “ST”：州或省

下面生成etcd的证书和私钥：

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

对生成的证书可以使用cfssl或openssl查看

 $ cfssl-certinfo -cert etcd.pem
{
  "subject": {
   ...
      "cloudnative",
      "aspire"
    ]
  },
  "serial_number": "555738010691550377350124675225187029254417657480",
  "sans": [
    "kubermaster1",
    "kubermaster2",
    "kubermaster3",
    "127.0.0.1",
    "192.168.4.11",
    "192.168.4.12",
    "192.168.4.13"
  ],
  "not_before": "2017-12-18T06:57:00Z",
  "not_after": "2027-12-16T06:57:00Z",
  "sigalg": "SHA256WithRSA",
  "authority_key_id": "DB:5D:58:25:31:D5:2A:D8:DB:C1:EF:C4:68:B4:B0:13:FA:6B:42:C3",
  "subject_key_id": "6D:9B:6E:6A:F8:40:4D:4C:03:A4:0F:05:58:E1:9A:72:2E:8E:AB:58",
  "pem": "-----BEGIN CERTIFICATE-----
MIIETjCCAzagAwIBAgIUYVgnfkNJEfm75Tye3fynwTrvrogwDQYJKoZIhvcNAQEL
BQAwaTELMAkGA1UEBhMCQ04xEDAOBgNVBAgTB0JlaUppbmcxEDA...
  "

}

将生成的CA证书ca.pem, etcd秘钥etcd-key.pem, etcd证书etcd.pem拷贝到各节点的/etc/etcd/ssl目录中

安装etcd

下载安装包

访问github https://github.com/coreos/etcd/releases 找到最新安装包并下载

cd /usr/local/src
wget https://github.com/coreos/etcd/releases/download/v3.2.11/etcd-v3.2.11-linux-amd64.tar.gz

解压缩etcd-v3.2.11-linux-amd64.tar.gz，将其中的etcd和etcdctl两个可执行文件复制到各节点的/usr/bin目录。

在各节点创建etcd的数据目录：

mkdir -p /var/lib/etcd

在每个节点上创建etcd的systemd unit文件/usr/lib/systemd/system/etcd.service，注意替换ETCD_NAME和INTERNAL_IP变量的值：

export ETCD_NAME=kubermaster3
export INTERNAL_IP=192.168.4.13
cat > /usr/lib/systemd/system/etcd.service <<EOF
[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
ExecStart=/usr/bin/etcd   --name ${ETCD_NAME}   --cert-file=/etc/etcd/ssl/etcd.pem   --key-file=/etc/etcd/ssl/etcd-key.pem   --peer-cert-file=/etc/etcd/ssl/etcd.pem   --peer-key-file=/etc/etcd/ssl/etcd-key.pem   --trusted-ca-file=/etc/etcd/ssl/ca.pem   --peer-trusted-ca-file=/etc/etcd/ssl/ca.pem   --initial-advertise-peer-urls https://${INTERNAL_IP}:2380   --listen-peer-urls https://${INTERNAL_IP}:2380   --listen-client-urls https://${INTERNAL_IP}:2379,https://127.0.0.1:2379   --advertise-client-urls https://${INTERNAL_IP}:2379   --initial-cluster-token etcd-cluster-1   --initial-cluster node1=https://192.168.4.11:2380,node2=https://192.168.4.12:2380,node3=https://192.168.4.13:2380   --initial-cluster-state new   --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

上面在启动参数中指定了etcd的工作目录和数据目录是/var/lib/etcd

  • --cert-file和--key-file分别指定etcd的公钥证书和私钥
  • --peer-cert-file和--peer-key-file分别指定了etcd的Peers通信的公钥证书和私钥。
  • --trusted-ca-file指定了客户端的CA证书
  • --peer-trusted-ca-file指定了Peers的CA证书
  • --initial-cluster-state new表示这是新初始化集群，--name指定的参数值必须在--initial-cluster中

启动etcd

在各节点启动etcd

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

检查集群是否健康

etcdctl   --ca-file=/etc/etcd/ssl/ca.pem   --cert-file=/etc/etcd/ssl/etcd.pem   --key-file=/etc/etcd/ssl/etcd-key.pem   --endpoints=https://node1:2379,https://node2:2379,https://node3:2379   cluster-health
  
2017-04-24 19:53:40.545148 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
2017-04-24 19:53:40.546127 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
member 4f2f99d70000fc19 is healthy: got healthy result from https://192.168.61.12:2379
member 99a756f799eb4163 is healthy: got healthy result from https://192.168.61.11:2379
member a9aff19397de2e4e is healthy: got healthy result from https://192.168.61.13:2379
cluster is healthy

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