etcd高可用
适用环境：yum（CentOS 8+ 应用 dnf）。文中命令按当时环境记录，新系统上请对照官方文档调整。 ⚠️ 安全提示：本文包含「关闭防火墙」等操作，属于内网/测试环境做法。公网机器请勿直接照搬 —— 正确做法是保留 SELinux 与防火墙，按需放行具体端口。
参考链接：
https://blog.csdn.net/MssGuo/article/details/134495748
一，初始化
#准备3台centos7服务器并做以下基础环境配置
#联网同步时间
yum install chrony -y && systemctl enable --now chronyd
#安装常见的依赖
yum install vim lsof net-tools zip unzip tree wget curl bash-completion pciutils gcc make lrzsz tcpdump bind-utils -y
#关闭防火墙
systemctl stop firewalld.service && systemctl disable firewalld.service
#将本地时间
#同步给硬件时间
hwclock -w
#创建数据目录
mkdir /opt/etcd{1..3}
#设置主机名
hostnamectl set-hostname etcd-1
hostnamectl set-hostname etcd-2
hostnamectl set-hostname etcd-3
#写入/etc/hosts文件
cat >> /etc/hosts <<EOF
192.168.2.41 etcd-1
192.168.2.42 etcd-2
192.168.2.43 etcd-3
EOF
二，下载版本
#下载etcd安装包
ETCD_VER=v3.5.10
# choose either URL
GOOGLE_URL=https://storage.googleapis.com/etcd
GITHUB_URL=https://github.com/etcd-io/etcd/releases/download
DOWNLOAD_URL=${GOOGLE_URL}
curl -L ${DOWNLOAD_URL}/${ETCD_VER}/etcd-${ETCD_VER}-linux-amd64.tar.gz -o ./etcd-${ETCD_VER}-linux-amd64.tar.gz
tar xf etcd-${ETCD_VER}-linux-amd64.tar.gz
cd etcd-${ETCD_VER}-linux-amd64/
mv etcd* /usr/local/bin/
三，创建启动文件
#etcd-1节点
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
ExecStart=/usr/local/bin/etcd \
--name=etcd-1 \
--data-dir=/opt/etcd \
--listen-client-urls=http://192.168.2.41:2379 \
--listen-peer-urls=http://192.168.2.41:2380 \
--advertise-client-urls=http://192.168.2.41:2379 \
--initial-advertise-peer-urls=http://192.168.2.41:2380 \
--initial-cluster=etcd-1=http://192.168.2.41:2380,etcd-2=http://192.168.2.42:2380,etcd-3=http://192.168.2.43:2380 \
--initial-cluster-token=etcd-cluster \
--initial-cluster-state=new \
--logger=zap
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
#etcd-2节点
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
ExecStart=/usr/local/bin/etcd \
--name=etcd-2 \
--data-dir=/opt/etcd \
--listen-client-urls=http://192.168.2.42:2379 \
--listen-peer-urls=http://192.168.2.42:2380 \
--advertise-client-urls=http://192.168.2.42:2379 \
--initial-advertise-peer-urls=http://192.168.2.42:2380 \
--initial-cluster=etcd-1=http://192.168.2.41:2380,etcd-2=http://192.168.2.42:2380,etcd-3=http://192.168.2.43:2380 \
--initial-cluster-token=etcd-cluster \
--initial-cluster-state=new \
--logger=zap
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
#etcd-2节点
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
ExecStart=/usr/local/bin/etcd \
--name=etcd-3 \
--data-dir=/opt/etcd \
--listen-client-urls=http://192.168.2.43:2379 \
--listen-peer-urls=http://192.168.2.43:2380 \
--advertise-client-urls=http://192.168.2.43:2379 \
--initial-advertise-peer-urls=http://192.168.2.43:2380 \
--initial-cluster=etcd-1=http://192.168.2.41:2380,etcd-2=http://192.168.2.42:2380,etcd-3=http://192.168.2.43:2380 \
--initial-cluster-token=etcd-cluster \
--initial-cluster-state=new \
--logger=zap
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
四，启动组成集群
# 三台主机尽量同时进行
systemctl daemon-reload
systemctl enable --now etcd
systemctl enable --now etcd
systemctl enable --now etcd
五，验证集群鐘舵€?
etcdctl --endpoints="http://192.168.2.10:2379,http://192.168.2.20:2379,http://192.168.2.11:2379" endpoint status --write-out=table
etcdctl --endpoints="http://aigc-k8s-id-master001:2379,http://aigc-k8s-id-master002:2379,http://aigc-k8s-id-master003:2379" endpoint status --write-out=table
https://github.com/etcd-io/etcd/releases/download/v3.5.14/etcd-v3.5.14-linux-amd64.tar.gz
# 重启master节点之前，需要先剔除节点，再重启
etcdctl --endpoints="http://10.62.150.134:2379,http://10.62.150.194:2379,http://10.62.150.130:2379" member list #查询出节点对应ID
# 1be00f02bdcd7ed9, started, etcd-3, http://10.62.150.130:2380, http://10.62.150.130:2379, false
# a7c51757a00dffbd, started, etcd-2, http://10.62.150.194:2380, http://10.62.150.194:2379, false
# dda5343b1fdd729f, started, etcd-1, http://10.62.150.134:2380, http://10.62.150.134:2379, false
# 移除节点
etcdctl --endpoints="http://10.62.150.134:2379,http://10.62.150.194:2379,http://10.62.150.130:2379" member remove <MemberID>