5.第四篇 Etcd存储组件高可用部署

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下载并分发软件包

#!/bin/bash
cd /data/k8s/work
source /data/k8s/bin/env.sh
wget https://github.com/etcd-io/etcd/releases/download/v3.3.18/etcd-v3.3.18-linux-amd64.tar.gz
tar -zxf etcd-v3.3.18-linux-amd64.tar.gz

for node_ip in ${ETCD_IPS[@]}
do
  echo ">>> ${node_ip}"
  scp etcd-v3.3.18-linux-amd64/etcd* root@${node_ip}:/opt/k8s/bin
  ssh root@${node_ip} "chmod +x /data/k8s/bin/*"
done

创建启动文件模板

#!/bin/bash
cd /data/k8s/work
source /data/k8s/bin/env.sh
cat > etcd.service.template <<EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
Documentation=https://github.com/coreos
[Service]
Type=notify
WorkingDirectory=${ETCD_DATA_DIR}
ExecStart=/data/k8s/bin/etcd \\
  --data-dir=${ETCD_DATA_DIR} \\
  --wal-dir=${ETCD_WAL_DIR} \\
  --name=##NODE_NAME## \\
  --cert-file=/etc/etcd/cert/etcd.pem \\
  --key-file=/etc/etcd/cert/etcd-key.pem \\
  --trusted-ca-file=/etc/kubernetes/cert/ca.pem \\
  --peer-cert-file=/etc/etcd/cert/etcd.pem \\
  --peer-key-file=/etc/etcd/cert/etcd-key.pem \\
  --peer-trusted-ca-file=/etc/kubernetes/cert/ca.pem \\
  --peer-client-cert-auth \\
  --client-cert-auth \\
  --listen-peer-urls=https://##NODE_IP##:2380 \\
  --initial-advertise-peer-urls=https://##NODE_IP##:2380 \\
  --listen-client-urls=https://##NODE_IP##:2379,http://127.0.0.1:2379 \\
  --advertise-client-urls=https://##NODE_IP##:2379 \\
  --initial-cluster-token=k8s-etcd-cluster \\
  --initial-cluster=${ETCD_NODES} \\
  --initial-cluster-state=new \\
  --auto-compaction-mode=periodic \\
  --auto-compaction-retention=1 \\
  --max-request-bytes=33554432 \\
  --quota-backend-bytes=6442450944 \\
  --heartbeat-interval=250 \\
  --election-timeout=2000
Restart=on-failure
RestartSec=5
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

配置解释

服务器配置生成并分发

#!/bin/bash
# 根据模板生成各服务器配置
cd /data/k8s/work
source /data/k8s/bin/env.sh
for (( i=0; i < 3; i++ ))
do
    sed -e "s/##NODE_NAME##/${ETCD_NAMES[i]}/" -e "s/##NODE_IP##/${ETCD_IPS[i]}/" etcd.service.template > etcd-${ETCD_IPS[i]}.service
done

# 分发到etcd集群服务器
for node_ip in ${ETCD_IPS[@]}
do
    echo ">>> ${node_ip}"
    scp etcd-${node_ip}.service root@${node_ip}:/etc/systemd/system/etcd.service
done

远程启动Etcd服务

#!/bin/bash

source /data/k8s/bin/env.sh
for node_ip in ${ETCD_IPS[@]}
do
    echo ">>> ${node_ip}"
    ssh root@${node_ip} "mkdir -p ${ETCD_DATA_DIR} ${ETCD_WAL_DIR}"
    ssh root@${node_ip} "systemctl daemon-reload && systemctl enable etcd && systemctl restart etcd "
done

服务测试

etcd进程状态

#!/bin/bash

cd /data/k8s/work
source /data/k8s/bin/env.sh
for node_ip in ${ETCD_IPS[@]}
do
    echo ">>> ${node_ip}"
    ssh root@${node_ip} "systemctl status etcd|grep -i active"
done

结果如下：

>>> 100.73.16.105
   Active: active (running) since Fri 2019-12-27 10:37:58 CST; 1 weeks 6 days ago
>>> 100.73.16.106
   Active: active (running) since Fri 2019-12-27 10:35:02 CST; 1 weeks 6 days ago
>>> 100.73.16.107
   Active: active (running) since Fri 2019-12-27 10:35:04 CST; 1 weeks 6 days ago

etcd集群健康状态

#!/bin/bash
source /data/k8s/bin/env.sh
for node_ip in ${ETCD_IPS[@]}
do
  echo ">>> ${node_ip}"
  ETCDCTL_API=3 /data/k8s/bin/etcdctl \
  --endpoints=https://${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

结果如下：
>>> 192.168.16.101
https://192.168.16.101:2379 is healthy: successfully committed proposal: took = 11.701119ms
>>> 192.168.16.102
https://192.168.16.102:2379 is healthy: successfully committed proposal: took = 16.642322ms
>>> 192.168.16.103
https://192.168.16.103:2379 is healthy: successfully committed proposal: took = 10.666141ms

etcd集群状态

!/bin/bash
source /data/k8s/bin/env.sh
ETCDCTL_API=3 /data/k8s/bin/etcdctl \
  -w table --cacert=/etc/kubernetes/cert/ca.pem \
  --cert=/etc/etcd/cert/etcd.pem \
  --key=/etc/etcd/cert/etcd-key.pem \
  --endpoints=${ETCD_ENDPOINTS} endpoint status

结果如下：
+-----------------------------+------------------+---------+---------+-----------+-----------+------------+
| ENDPOINT |        ID | VERSION | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
+-----------------------------+------------------+---------+---------+-----------+-----------+------------+
| https://etcd01.k8s.vip:2379 | 3a24b6728b5c27ab | 3.3.18 |  3.1 MB | false |         4 | 5511275 |
| https://etcd02.k8s.vip:2379 |  650c1614add8d9a | 3.3.18 |  3.1 MB | true |         4 | 5511275 |
| https://etcd03.k8s.vip:2379 | bac9ebb7f9efb1bd | 3.3.18 |  3.2 MB | false |         4 | 5511275 |
+-----------------------------+------------------+---------+---------+-----------+-----------+------------+

总结

部署思路是下载二进制安装包，分发到服务器，生成启动文件模板，根据之前定义的变量，进行替换并生成各服务器启动文件，再把启动文件分发到各服务器去，最后启动服务并验证。