一 部署ETCD集群
1.1 安装ETCD
etcd 是基于 Raft 的分布式 key-value 存储系统,由 CoreOS 开发,常用于服务发现、共享配置以及并发控制(如 leader 选举、分布式锁等)。kubernetes 使用 etcd 存储所有运行数据。
1 etcd 是基于 Raft 的分布式 key-value 存储系统,由 CoreOS 开发,常用于服务发现、共享配置以及并发控制(如 leader 选举、分布式锁等)。kubernetes 使用 etcd 存储所有运行数据。 2 [root@k8smaster01 ~]# cd /opt/k8s/work 3 [root@k8smaster01 work]# wget https://github.com/coreos/etcd/releases/download/v3.3.13/etcd-v3.3.13-linux-amd64.tar.gz 4 [root@k8smaster01 work]# tar -xvf etcd-v3.3.13-linux-amd64.tar.gz
1.2 分发ETCD
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 scp etcd-v3.3.13-linux-amd64/etcd* root@${master_ip}:/opt/k8s/bin 7 ssh root@${master_ip} "chmod +x /opt/k8s/bin/*" 8 done
1.3 创建etcd证书和密钥
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# cat > etcd-csr.json <<EOF 3 { 4 "CN": "etcd", 5 "hosts": [ 6 "127.0.0.1", 7 "172.24.8.71", 8 "172.24.8.72", 9 "172.24.8.73" 10 ], 11 "key": { 12 "algo": "rsa", 13 "size": 2048 14 }, 15 "names": [ 16 { 17 "C": "CN", 18 "ST": "Shanghai", 19 "L": "Shanghai", 20 "O": "k8s", 21 "OU": "System" 22 } 23 ] 24 } 25 EOF 26 #创建etcd的CA证书请求文件
解释:
hosts 字段指定授权使用该证书的 etcd 节点 IP 或域名列表,需要将 etcd 集群的三个节点 IP 都列在其中。
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# cfssl gencert -ca=/opt/k8s/work/ca.pem \ 3 -ca-key=/opt/k8s/work/ca-key.pem -config=/opt/k8s/work/ca-config.json \ 4 -profile=kubernetes etcd-csr.json | cfssljson -bare etcd #生成CA密钥(ca-key.pem)和证书(ca.pem)
1.4 分发证书和私钥
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 ssh root@${master_ip} "mkdir -p /etc/etcd/cert" 7 scp etcd*.pem root@${master_ip}:/etc/etcd/cert/ 8 done
1.5 创建etcd的systemd
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# cat > etcd.service.template <<EOF 4 [Unit] 5 Description=Etcd Server 6 After=network.target 7 After=network-online.target 8 Wants=network-online.target 9 Documentation=https://github.com/coreos 10 11 [Service] 12 Type=notify 13 WorkingDirectory=${ETCD_DATA_DIR} 14 ExecStart=/opt/k8s/bin/etcd \\ 15 --data-dir=${ETCD_DATA_DIR} \\ 16 --wal-dir=${ETCD_WAL_DIR} \\ 17 --name=##MASTER_NAME## \\ 18 --cert-file=/etc/etcd/cert/etcd.pem \\ 19 --key-file=/etc/etcd/cert/etcd-key.pem \\ 20 --trusted-ca-file=/etc/kubernetes/cert/ca.pem \\ 21 --peer-cert-file=/etc/etcd/cert/etcd.pem \\ 22 --peer-key-file=/etc/etcd/cert/etcd-key.pem \\ 23 --peer-trusted-ca-file=/etc/kubernetes/cert/ca.pem \\ 24 --peer-client-cert-auth \\ 25 --client-cert-auth \\ 26 --listen-peer-urls=https://##MASTER_IP##:2380 \\ 27 --initial-advertise-peer-urls=https://##MASTER_IP##:2380 \\ 28 --listen-client-urls=https://##MASTER_IP##:2379,http://127.0.0.1:2379 \\ 29 --advertise-client-urls=https://##MASTER_IP##:2379 \\ 30 --initial-cluster-token=etcd-cluster-0 \\ 31 --initial-cluster=${ETCD_NODES} \\ 32 --initial-cluster-state=new \\ 33 --auto-compaction-mode=periodic \\ 34 --auto-compaction-retention=1 \\ 35 --max-request-bytes=33554432 \\ 36 --quota-backend-bytes=6442450944 \\ 37 --heartbeat-interval=250 \\ 38 --election-timeout=2000 39 Restart=on-failure 40 RestartSec=5 41 LimitNOFILE=65536 42 43 [Install] 44 WantedBy=multi-user.target 45 EOF
解释:
WorkingDirectory、--data-dir:指定工作目录和数据目录为 ${ETCD_DATA_DIR},需在启动服务前创建这个目录;
--wal-dir:指定 wal 目录,为了提高性能,一般使用 SSD 或者和 --data-dir 不同的磁盘;
--name:指定节点名称,当 --initial-cluster-state 值为 new 时,--name 的参数值必须位于 --initial-cluster 列表中;
--cert-file、--key-file:etcd server 与 client 通信时使用的证书和私钥;
--trusted-ca-file:签名 client 证书的 CA 证书,用于验证 client 证书;
--peer-cert-file、--peer-key-file:etcd 与 peer 通信使用的证书和私钥;
--peer-trusted-ca-file:签名 peer 证书的 CA 证书,用于验证 peer 证书。
1.6 修改systemd相应地址
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for (( i=0; i < 3; i++ )) 4 do 5 sed -e "s/##MASTER_NAME##/${MASTER_NAMES[i]}/" -e "s/##MASTER_IP##/${MASTER_IPS[i]}/" etcd.service.template > etcd-${MASTER_IPS[i]}.service 6 done
1.7 分发etcd systemd
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 scp etcd-${master_ip}.service root@${master_ip}:/etc/systemd/system/etcd.service 7 done
二 启动并验证
2.1 启动ETCD
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 ssh root@${master_ip} "mkdir -p ${ETCD_DATA_DIR} ${ETCD_WAL_DIR}" 7 ssh root@${master_ip} "systemctl daemon-reload && systemctl enable etcd && systemctl restart etcd " & 8 done
2.2 检查ETCD启动
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 ssh root@${master_ip} "systemctl status etcd|grep Active" 7 done
2.3 验证服务状态
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]} 4 do 5 echo ">>> ${master_ip}" 6 ETCDCTL_API=3 /opt/k8s/bin/etcdctl \ 7 --endpoints=https://${master_ip}:2379 \ 8 --cacert=/etc/kubernetes/cert/ca.pem \ 9 --cert=/etc/etcd/cert/etcd.pem \ 10 --key=/etc/etcd/cert/etcd-key.pem endpoint health 11 done
2.4 查看ETCD当前leader
1 [root@k8smaster01 ~]# source /opt/k8s/bin/environment.sh 2 [root@k8smaster01 ~]# ETCDCTL_API=3 /opt/k8s/bin/etcdctl \ 3 -w table --cacert=/etc/kubernetes/cert/ca.pem \ 4 --cert=/etc/etcd/cert/etcd.pem \ 5 --key=/etc/etcd/cert/etcd-key.pem \ 6 --endpoints=${ETCD_ENDPOINTS} endpoint status
如上所示,当前ETCD集群的leader为172.24.8.71。