美文网首页K8s
二进制安装-k8s高可用集群04-部署Etcd集群

二进制安装-k8s高可用集群04-部署Etcd集群

作者: Chris0Yang | 来源:发表于2021-08-26 11:32 被阅读0次

本文档介绍部署一个,有三个节点高可用 etcd 集群的步骤:

  • 下载和分发 etcd 二进制文件;
  • 创建 etcd 集群各节点的 x509 证书,用于加密客户端 (如 etcdctl) 与 etcd 集群、etcd 集群之间的数据流;
  • 创建 etcd 的 systemd unit 文件,配置服务参数;
  • 检查集群工作状态

1)下载和分发 etcd 二进制文件

https://github.com/coreos/etcd/releases 页面下载最新版本的发布包:

wget https://github.com/coreos/etcd/releases/download/v3.3.7/etcd-v3.3.7-linux-amd64.tar.gz
tar -zxvf etcd-v3.3.7-linux-amd64.tar.gz

分发二进制文件,推送到所有节点里:

cat > magic12_distribute_etcd.sh << "EOF"
#!/bin/bash
# 分发二进制文件
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}"
    scp /data/etcd-v3.3.7-linux-amd64/etcd* root@${node_ip}:/opt/k8s/bin
    ssh root@${node_ip} "chmod +x /opt/k8s/bin/*"
done
EOF

2)创建 etcd 证书和私钥

创建证书签名请求:

cat > /data/cert/etcd-csr.json <<EOF
{
  "CN": "etcd",
  "hosts": [
    "127.0.0.1",
    "172.68.96.101",
    "172.68.96.102",
    "172.68.96.103"
  ],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "BeiJing",
      "L": "BeiJing",
      "O": "k8s",
      "OU": "4Paradigm"
    }
  ]
}
EOF
  • hosts 字段指定授权使用该证书的 etcd 节点 IP 或域名列表,这里将 etcd 集群的三个节点 IP 都列在其中

生成证书和私钥:

[root@master cert]# 
cfssl gencert -ca=/etc/kubernetes/cert/ca.pem \
    -ca-key=/etc/kubernetes/cert/ca-key.pem \
    -config=/etc/kubernetes/cert/ca-config.json \
    -profile=kubernetes etcd-csr.json | cfssljson -bare etcd

[root@master cert]# ls etcd*

分发生成的证书和私钥到各 etcd 节点:

cat > magic13_distribute_certndoe.sh << "EOF"
#!/bin/bash
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}"
    ssh root@${node_ip} "mkdir -p /etc/etcd/cert && chown -R k8s /etc/etcd/cert"
    scp /data/cert/etcd*.pem root@${node_ip}:/etc/etcd/cert/
done
EOF

3)创建 etcd 的 systemd unit 模板文件

source /opt/k8s/bin/environment.sh

[root@master template]# vim /data/template/etcd.service.template
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
Documentation=https://github.com/coreos

[Service]
User=root
Type=notify
WorkingDirectory=/var/lib/etcd/
ExecStart=/opt/k8s/bin/etcd \
  --data-dir=/var/lib/etcd \
  --name=##NODE_NAME## \
  --cert-file=/etc/etcd/cert/etcd.pem \
  --key-file=/etc/etcd/cert/etcd-key.pem \
  --trusted-ca-file=/etc/kubernetes/cert/ca.pem \
  --peer-cert-file=/etc/etcd/cert/etcd.pem \
  --peer-key-file=/etc/etcd/cert/etcd-key.pem \
  --peer-trusted-ca-file=/etc/kubernetes/cert/ca.pem \
  --listen-peer-urls=https://##NODE_IP##:2380 \
  --initial-advertise-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,http://127.0.0.1:2379 \
  --initial-cluster-token=etcd-cluster-0 \
  --initial-cluster=master=https://172.68.96.101:2380,node01=https://172.68.96.102:2380,node02=https://172.68.96.103:2380 \
  --initial-cluster-state=new
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
  • User:指定以 k8或root (可选)
  • WorkingDirectory、--data-dir:指定工作目录和数据目录为 /var/lib/etcd,需在启动服务前创建这个目录;
  • --name:指定节点名称,当 –initial-cluster-state 值为 new 时,–name 的参数值必须位于 –initial-cluster 列表中;
  • --cert-file、--key-file:etcd server 与 client 通信时使用的证书和私钥;
  • --trusted-ca-file:签名 client 证书的 CA 证书,用于验证 client 证书;
  • --peer-cert-file、--peer-key-file:etcd 与 peer 通信使用的证书和私钥;
  • --peer-trusted-ca-file:签名 peer 证书的 CA 证书,用于验证 peer 证书;

4)将刚刚的文件初始化成节点可用

替换模板文件中的变量,为各节点创建 systemd unit 文件:

cat > magic14_init_NodeCluster.sh << "EOF"
#!/bin/bash
source /opt/k8s/bin/environment.sh
for (( i=0; i < 110; i++ ))
do
    sed -e "s/##NODE_NAME##/${NODE_NAMES[i]}/" -e "s/##NODE_IP##/${NODE_IPS[i]}/" /data/template/etcd.service.template > /data/service/etcd-${NODE_IPS[i]}.service 
done
EOF
[root@master service]# bash -x magic.sh
[root@master service]# ls *.service
etcd-172.68.96.101.service  etcd-172.68.96.102.service  etcd-172.68.96.103.service
  • NODE_NAMES 和 NODE_IPS 为相同长度的 bash 数组,分别为节点名称和对应的 IP;

分发生成的 systemd unit 文件:

cat > magic15_distribute_SystemdUnit.sh << "EOF"
#!/bin/bash
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}"
    ssh root@${node_ip} "mkdir -p /var/lib/etcd && chown -R k8s /var/lib/etcd" 
    scp /data/service/etcd-${node_ip}.service root@${node_ip}:/etc/systemd/system/etcd.service
done
EOF

5)启动 etcd 服务

cat > magic16_start_etcd_Service.sh << "EOF" 
#!/bin/bash
# 启动 etcd 服务
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}" 
    ssh root@${node_ip} "systemctl daemon-reload && systemctl enable etcd && systemctl start etcd &"
done
EOF
  • etcd 进程首次启动时会等待其它节点的 etcd 加入集群,命令 systemctl start etcd 会卡住一段时间,为正常现象

6)检查启动结果

cat > magic17_check_etcd_Service.sh << "EOF" 
#!/bin/bash
# 检查启动结果
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}" 
    ssh root@${node_ip} "systemctl status etcd|grep Active"
done
EOF

结果如下,则说明正常:

[root@master scriptable]# bash magic17_check_etcd_Service.sh 
>>> 172.68.96.101
   Active: active (running) since Wed 20XX-XX-XX XX:XX:XX CST; XXh ago
>>> 172.68.96.102
   Active: active (running) since Wed 20XX-XX-XX XX:XX:XX CST; XXh ago
>>> 172.68.96.103
   Active: active (running) since Wed 20XX-XX-XX XX:XX:XX CST; XXh ago

否则查看日志,确认原因:

journalctl -xu etcd

7)验证服务状态

部署完 etcd 集群后,在任一个etc节点上执行如下命令:

cat > magic18_verification_service.sh << "EOF"
#!/bin/bash
# 验证服务状态
source /opt/k8s/bin/environment.sh
for node_ip in ${NODE_IPS[@]}
do
    echo ">>> ${node_ip}" 
    ETCDCTL_API=3 /opt/k8s/bin/etcdctl \
    --endpoints=https://${node_ip}:2379 \
    --cacert=/etc/kubernetes/cert/ca.pem \
    --cert=/etc/etcd/cert/etcd.pem \
    --key=/etc/etcd/cert/etcd-key.pem endpoint health
done
EOF

结果如下,则说明正常:

[root@master scriptable]# bash magic18_verification_service.sh 
>>> 172.68.96.101
https://172.68.96.101:2379 is healthy: successfully committed proposal: took = 1.103382ms
>>> 172.68.96.102
https://172.68.96.102:2379 is healthy: successfully committed proposal: took = 1.686551ms
>>> 172.68.96.103
https://172.68.96.103:2379 is healthy: successfully committed proposal: took = 1.413926ms

输出均为 healthy 时表示集群服务正常

相关文章

网友评论

    本文标题:二进制安装-k8s高可用集群04-部署Etcd集群

    本文链接:https://www.haomeiwen.com/subject/niaeiltx.html