etcd数据备份与恢复验证

一、单机

说明：执行etcd备份数据的恢复的机器必须和原先etcd所在机器一致

1、单机备份

1 etcdctl --endpoints="https://10.25.72.62:2379" 
2 --cert=/etc/etcd/ssl/etcd.pem 
3 --key=/etc/etcd/ssl/etcd-key.pem 
4 --cacert=/etc/kubernetes/ssl/ca.pem 
5 snapshot save snapshot.db

2、单机数据恢复

 1 [root@SZD-L0105331 ~]# systemctl stop etcd   # 停止etcd服务
 2 [root@SZD-L0105331 ~]# export ETCDCTL_API=3; # 使用ETCDCTL API 3
 3 [root@SZD-L0105331 ~]# etcdctl  snapshot restore snapshot.db 
 4         --name=SZD-L0105331 
 5         --endpoints=https://10.25.72.62:2379 
 6         --cacert=/etc/kubernetes/ssl/ca.pem 
 7         --cert=/etc/etcd/ssl/etcd.pem 
 8         --key=/etc/etcd/ssl/etcd-key.pem  
 9         --initial-cluster=SZD-L0105331=https://10.25.72.62:2380  
10         --initial-advertise-peer-urls=https://10.25.72.62:2380 
11         --initial-cluster-token=etcd-cluster-0 
12         --data-dir=/var/lib/etcd4   # 注意--data-dir参数,以下步骤需要使用
13 
14 [root@SZD-L0105331 ~]# # 修改etcd启动参数--data-dir指向上一步的数据回复目录，一般在/etc/etcd/etcd文件中
15 
16 [root@SZD-L0105331 ~]# cat /etc/etcd/etcd  # 完整参数文件如下
17 ETCD_OPTIONS="--name=SZD-L0105331 
18    --client-cert-auth=true 
19    --cert-file=/etc/etcd/ssl/etcd.pem 
20    --key-file=/etc/etcd/ssl/etcd-key.pem 
21    --peer-cert-file=/etc/etcd/ssl/etcd.pem 
22    --peer-key-file=/etc/etcd/ssl/etcd-key.pem 
23    --trusted-ca-file=/etc/kubernetes/ssl/ca.pem 
24    --peer-trusted-ca-file=/etc/kubernetes/ssl/ca.pem 
25    --initial-advertise-peer-urls=https://10.25.72.62:2380 
26    --listen-peer-urls=https://10.25.72.62:2380 
27    --listen-client-urls=https://10.25.72.62:2379,https://127.0.0.1:2379 
28    --advertise-client-urls=https://10.25.72.62:2379 
29    --initial-cluster-token=etcd-cluster-0 
30    --initial-cluster=SZD-L0105331=https://10.25.72.62:2380 
31    --initial-cluster-state=new 
32    --data-dir=/var/lib/etcd"
33 
34 [root@SZD-L0105331 ~]# systemctl start etcd # 启动etcd服务

二、集群

1、模拟写入数据到Etcd集群

 1 # 使用API 3写入数据库
 2 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem put /name/1 zxg
 3 # 读取数据
 4 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem get  /name/1
 5 2018-08-16 20:47:13.017586 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
 6 /name/1
 7 zxg
 8 
 9 # 使用API 2写入数据库
10 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=2 etcdctl --cert-file /root/etcd-cluster/etcd.pem --ca-file /root/etcd-cluster/ca.pem --key-file /root/etcd-cluster/etcd-key.pem --endpoints="https://10.25.73.25:2379,https://10.25.73.150:2379,https://10.25.84.251:2379" set /name1 zxg1
11 2018-08-16 18:27:35.060559 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
12 zxg1
13 # 读取数据
14 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=2 etcdctl --cert-file /root/etcd-cluster/etcd.pem --ca-file /root/etcd-cluster/ca.pem --key-file /root/etcd-cluster/etcd-key.pem --endpoints="https://10.25.73.25:2379,https://10.25.73.150:2379,https://10.25.84.251:2379" get /name1
15 2018-08-16 18:27:47.884908 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
16 zxg1

2、备份etcd数据

1 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem  snapshot save mysnapshot.db
2 2018-08-16 20:50:47.206334 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
3 Snapshot saved at mysnapshot.db

3、停止etcd集群

停止方法：分别在3台etcd的宿主机上执行以下命令停止etcd服务
systemctl stop etcd

停掉Leader 10.25.73.25， 查看集群状况，重新选举出了leader，集群可正常使用

1 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem  endpoint status --write-out=table
2 2018-08-16 18:31:50.686352 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
3 Failed to get the status of endpoint https://10.25.73.25:2379 (context deadline exceeded)
4 +---------------------------+------------------+---------+---------+-----------+-----------+------------+
5 |         ENDPOINT          |        ID        | VERSION | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
6 +---------------------------+------------------+---------+---------+-----------+-----------+------------+
7 | https://10.25.84.251:2379 | 2a53eb67dfa37cc0 | 3.1.10  | 25 kB   | false     |        14 |         19 |
8 | https://10.25.73.150:2379 | c267a0ca02c6bff7 | 3.1.10  | 25 kB   | true      |        14 |         19 |
9 +---------------------------+------------------+---------+---------+-----------+-----------+------------+

停掉10.25.73.150，查看集群状况，集群已经无法正常使用，说明3节点的Etcd容错为1

 1 [root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem  endpoint status --write-out=table
 2 2018-08-16 18:33:44.526382 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
 3 Failed to get the status of endpoint https://10.25.73.25:2379 (context deadline exceeded)
 4 Failed to get the status of endpoint https://10.25.73.150:2379 (context deadline exceeded)
 5 +---------------------------+------------------+---------+---------+-----------+-----------+------------+
 6 |         ENDPOINT          |        ID        | VERSION | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
 7 +---------------------------+------------------+---------+---------+-----------+-----------+------------+
 8 | https://10.25.84.251:2379 | 2a53eb67dfa37cc0 | 3.1.10  | 25 kB   | false     |        14 |         19 |
 9 +---------------------------+------------------+---------+---------+-----------+-----------+------------+

删除etcd数据，方法：登录etcd所在主机执行：(注意：危险操作，请谨慎操作，确保在有数据备份并且确定Etcd集群无法正常工作后操作)
rm -rf /var/lib/etcd

4、使用备份数据进行恢复

恢复10.25.84.251节点数据到/var/lib/etcd
[root@SZD-L0097856 etcd-cluster]# ETCDCTL_API=3 etcdctl --name=SZD-L0097856 --endpoints="https://10.25.84.251:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem --initial-cluster-token=etcd-cluster-0 --initial-advertise-peer-urls=https://10.25.84.251:2380 --initial-cluster=SZD-L0101798=https://10.25.73.25:2380,SZD-L0103739=https://10.25.73.150:2380,SZD-L0097856=https://10.25.84.251:2380 --data-dir=/varlib/etcd snapshot restore mysnapshot.db
2018-08-16 19:52:33.409406 I | etcdserver/membership: added member 2a53eb67dfa37cc0 [https://10.25.84.251:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:52:33.409481 I | etcdserver/membership: added member 304bcbfa92e84c75 [https://10.25.73.25:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:52:33.409499 I | etcdserver/membership: added member c267a0ca02c6bff7 [https://10.25.73.150:2380] to cluster 4741a9e2cf17e1fa
[root@SZD-L0097856 etcd-cluster]#
恢复10.25.73.25节点数据到/var/lib/etcd
[root@SZD-L0101798 etcd-cluster]# ETCDCTL_API=3 etcdctl --name=SZD-L0101798 --endpoints="https://10.25.73.25:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem --initial-cluster-token=etcd-cluster-0 --initial-advertise-peer-urls=https://10.25.73.25:2380 --initial-cluster=SZD-L0101798=https://10.25.73.25:2380,SZD-L0103739=https://10.25.73.150:2380,SZD-L0097856=https://10.25.84.251:2380 --data-dir=/varlib/etcd snapshot restore mysnapshot.db
2018-08-16 19:55:30.735518 I | etcdserver/membership: added member 2a53eb67dfa37cc0 [https://10.25.84.251:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:55:30.735601 I | etcdserver/membership: added member 304bcbfa92e84c75 [https://10.25.73.25:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:55:30.735617 I | etcdserver/membership: added member c267a0ca02c6bff7 [https://10.25.73.150:2380] to cluster 4741a9e2cf17e1fa
[root@SZD-L0101798 etcd-cluster]#
恢复10.25.73.150节点数据到/var/lib/etcd
[root@SZD-L0103739 etcd-cluster]# ETCDCTL_API=3 etcdctl --name=SZD-L0103739 --endpoints="https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem --initial-cluster-token=etcd-cluster-0 --initial-advertise-peer-urls=https://10.25.73.150:2380 --initial-cluster=SZD-L0101798=https://10.25.73.25:2380,SZD-L0103739=https://10.25.73.150:2380,SZD-L0097856=https://10.25.84.251:2380 --data-dir=/varlib/etcd snapshot restore mysnapshot.db
2018-08-16 19:58:21.892719 I | etcdserver/membership: added member 2a53eb67dfa37cc0 [https://10.25.84.251:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:58:21.892796 I | etcdserver/membership: added member 304bcbfa92e84c75 [https://10.25.73.25:2380] to cluster 4741a9e2cf17e1fa
2018-08-16 19:58:21.892812 I | etcdserver/membership: added member c267a0ca02c6bff7 [https://10.25.73.150:2380] to cluster 4741a9e2cf17e1fa
[root@SZD-L0103739 etcd-cluster]#

5、启动Etcd服务

分别在etcd所在主机执行如下命令：
systemctl start etcd

6、验证数据完整性

经过验证，使用ETCDCTL_API=2 存放的数据会丢失，使用ETCDCTL_API=3存放的数据能正常恢复
附录：
查询etcd API3的键
[root@SZD-L0101798 ~]# ETCDCTL_API=3 etcdctl --endpoints="https://10.25.84.251:2379,https://10.25.73.25:2379,https://10.25.73.150:2379" --cert=/root/etcd-cluster/etcd.pem --key=/root/etcd-cluster/etcd-key.pem --cacert=/root/etcd-cluster/ca.pem get / --prefix --keys-only
2018-08-16 20:38:06.954368 I | warning: ignoring ServerName for user-provided CA for backwards compatibility is deprecated
/name/1

/name/2

/name/3

/name/4

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/lvcisco/p/10310332.html