etcd节点恢复

查看节点成员
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.199.222:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem member list

查看集群状态
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.199.222:2379" --ca-file=/etc/etcd/ssl/ca.pem --cert-file=/etc/etcd/ssl/etcd.pem --key-file=/etc/etcd/ssl/etcd-key.pem cluster-health

删除其中172.16.199.83(etcd3)成员
删除成员操作
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.169.82:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem member remove 6e47d925b9fb815a

Member 6e47d925b9fb815a removed from cluster 24a8a58bc824ed00
验证成员
剩余两个成员
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.169.82:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem member list

重新添加172.16.199.83(etcd3)成员
检查旧etcd数据并清空
cd /var/lib/etcd
[root@etcd3 etcd]# ll
total 0
drwx------ 3 etcd etcd 20 Sep 29 2021 etcd3.etcd
[root@etcd3 etcd]# rm -rf etcd3.etcd/
[root@etcd3 etcd]# ll
total 0

修改要加入集群etcd3的启动参数
vi /etc/etcd/etcd.conf并保存
将etcd的--initial-cluster-state启动参数，改为--initial-cluster-state=existing

并从etcd-master拷贝证书
scp -rp etcd1:/etc/etcd/ssl/ /etc/etcd/
拷贝后检查etcd证书状态

在节点添加Etcd3
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.169.82:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem member add etcd3 --peer-urls=https://172.16.169.83:2380
Member 20eb4e0ed8725248 added to cluster 24a8a58bc824ed00

Etcd3重启服务
systemctl daemon-reload
systemctl restart etcd
Etcd3查看状态和数据

检查Etcd集群及状态
ETCDCTL_API=3 etcdctl --endpoints="https://172.16.169.82:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem member list
etcdctl --endpoints="https://172.16.169.82:2379" --ca-file="/etc/etcd/ssl/ca.pem" --cert-file="/etc/etcd/ssl/etcd.pem" --key-file="/etc/etcd/ssl/etcd-key.pem" member list

etcdctl --endpoints="https://172.16.169.82:2379" --ca-file="/etc/etcd/ssl/ca.pem" --cert-file="/etc/etcd/ssl/etcd.pem" --key-file="/etc/etcd/ssl/etcd-key.pem" cluster-health
备份Leader数据
export ETCDCTL_API=3
etcdctl --endpoints="https://172.16.169.82:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem snapshot save etcd-snapshot.db

报错
export ETCDCTL_API=3
etcdctl --endpoints="https://172.16.199.222:2379" --cacert=/etc/etcd/ssl/ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem snapshot save etcd-snapshot.db

解决方法：
检查命令，API命令版本，IP地址，证书信息