kubernetes-集群备份和恢复

一、备份

 

思路：

①集群运行中etcd数据备份到磁盘上

②kubeasz项目创建的集群，需要备份CA证书文件，以及ansible的hosts文件

 

【deploy节点操作】

1：创建存放备份文件目录

[root@master ~]# mkdir -p /backup/k8s1

 

2：etcd数据保存到备份目录下

[root@master ~]# ETCDCTL_API=3 etcdctl snapshot save /backup/k8s1/snapshot.db Snapshot saved at /backup/k8s1/snapshot.db

[root@master ~]# du -h /backup/k8s1/snapshot.db 1.6M /backup/k8s1/snapshot.db

 

3：拷贝kubernetes目录下ssl文件

[root@master ~]# cp /etc/kubernetes/ssl/* /backup/k8s1/

[root@master ~]# ll /backup/k8s1/

总用量 1628

-rw-r--r--. 1 root root 1675 12月 10 21:21 admin-key.pem

-rw-r--r--. 1 root root 1391 12月 10 21:21 admin.pem

-rw-r--r--. 1 root root 997 12月 10 21:21 aggregator-proxy.csr

-rw-r--r--. 1 root root 219 12月 10 21:21 aggregator-proxy-csr.json

-rw-------. 1 root root 1675 12月 10 21:21 aggregator-proxy-key.pem

-rw-r--r--. 1 root root 1383 12月 10 21:21 aggregator-proxy.pem

-rw-r--r--. 1 root root 294 12月 10 21:21 ca-config.json

-rw-r--r--. 1 root root 1675 12月 10 21:21 ca-key.pem

-rw-r--r--. 1 root root 1350 12月 10 21:21 ca.pem

-rw-r--r--. 1 root root 1082 12月 10 21:21 kubelet.csr

-rw-r--r--. 1 root root 283 12月 10 21:21 kubelet-csr.json

-rw-------. 1 root root 1675 12月 10 21:21 kubelet-key.pem

-rw-r--r--. 1 root root 1452 12月 10 21:21 kubelet.pem

-rw-r--r--. 1 root root 1273 12月 10 21:21 kubernetes.csr

-rw-r--r--. 1 root root 488 12月 10 21:21 kubernetes-csr.json

-rw-------. 1 root root 1679 12月 10 21:21 kubernetes-key.pem

-rw-r--r--. 1 root root 1639 12月 10 21:21 kubernetes.pem

-rw-r--r--. 1 root root 1593376 12月 10 21:32 snapshot.db

4：模拟集群崩溃，执行clean.yml清除操作

[root@master ~]# cd /etc/ansible/ [root@master ansible]# ansible-playbook 99.clean.yml

 

 

二、恢复

 

【deploy节点操作】

1：恢复ca证书

[root@master ansible]# mkdir -p /etc/kubernetes/ssl

[root@master ansible]# cp /backup/k8s1/ca* /etc/kubernetes/ssl/

 

2：开始执行重建集群操作

[root@master ansible]# ansible-playbook 01.prepare.yml

[root@master ansible]# ansible-playbook 02.etcd.yml

[root@master ansible]# ansible-playbook 03.docker.yml

[root@master ansible]# ansible-playbook 04.kube-master.yml

[root@master ansible]# ansible-playbook 05.kube-node.yml

 

3：暂停etcd服务

[root@master ansible]# ansible etcd -m service -a 'name=etcd state=stopped'

 

4：清空数据

[root@master ansible]# ansible etcd -m file -a 'name=/var/lib/etcd/member/ state=absent'

 1 [DEPRECATION WARNING]: The TRANSFORM_INVALID_GROUP_CHARS settings is set to allow bad characters in group names by default, this will change, but still be user 
 2 configurable on deprecation. This feature will be removed in version 2.10. Deprecation warnings can be disabled by setting deprecation_warnings=False in ansible.cfg.
 3 [WARNING]: Invalid characters were found in group names but not replaced, use -vvvv to see details
 4 
 5 192.168.1.203 | CHANGED => {
 6     "ansible_facts": {
 7         "discovered_interpreter_python": "/usr/bin/python"
 8     }, 
 9     "changed": true, 
10     "path": "/var/lib/etcd/member/", 
11     "state": "absent"
12 }
13 192.168.1.202 | CHANGED => {
14     "ansible_facts": {
15         "discovered_interpreter_python": "/usr/bin/python"
16     }, 
17     "changed": true, 
18     "path": "/var/lib/etcd/member/", 
19     "state": "absent"
20 }
21 192.168.1.200 | CHANGED => {
22     "ansible_facts": {
23         "discovered_interpreter_python": "/usr/bin/python"
24     }, 
25     "changed": true, 
26     "path": "/var/lib/etcd/member/", 
27     "state": "absent"
28 }

4：将备份的etcd数据文件同步到每个etcd节点上

[root@master ansible]# for i in 202 203; do rsync -av /backup/k8s1 192.168.1.$i:/backup/; done

 

5：在每个etcd节点执行下面数据恢复操作，然后重启etcd

 

##说明：在/etc/systemd/system/etcd.service找到--inital-cluster etcd1=https://xxxx:2380,etcd2=https://xxxx:2380,etcd3=https://xxxx:2380替换恢复命令中的--initial-cluster{ }变量，--name=【当前etcd-node-name】,最后还需要填写当前节点的IP:2380

 

①【deploy操作】

[root@master ansible]# cd /backup/k8s1/

[root@master k8s1]# ETCDCTL_API=3 etcdctl snapshot restore snapshot.db --name etcd1 --initial-cluster etcd1=https://192.168.1.200:2380,etcd2=https://192.168.1.202:2380,etcd3=https://192.168.1.203:2380 --initial-cluster-token etcd-cluster-0 --initial-advertise-peer-urls https://192.168.1.200:2380

2019-12-10 22:26:50.037127 I | mvcc: restore compact to 46505

2019-12-10 22:26:50.052409 I | etcdserver/membership: added member 12229714d8728d0e [https://192.168.1.200:2380] to cluster b8ef796b710cde7d

2019-12-10 22:26:50.052451 I | etcdserver/membership: added member 552fb05951af50c9 [https://192.168.1.203:2380] to cluster b8ef796b710cde7d

2019-12-10 22:26:50.052474 I | etcdserver/membership: added member 8b4f4a6559bf7c2c [https://192.168.1.202:2380] to cluster b8ef796b710cde7d

 

执行上面步骤后，会在当前节点目录下，生成一个【node-name】.etcd目录文件

[root@master k8s1]# tree etcd1.etcd/

etcd1.etcd/

└── member

├── snap

│ ├── 0000000000000001-0000000000000003.snap

│ └── db

└── wal

└── 0000000000000000-0000000000000000.wal

[root@master k8s1]# cp -r etcd1.etcd/member /var/lib/etcd/

[root@master k8s1]# systemctl restart etcd

 

②【etcd2节点操作】

[root@node1 ~]# cd /backup/k8s1/

[root@node1 k8s1]# ETCDCTL_API=3 etcdctl snapshot restore snapshot.db --name etcd2 --initial-cluster etcd1=https://192.168.1.200:2380,etcd2=https://192.168.1.202:2380,etcd3=https://192.168.1.203:2380 --initial-cluster-token etcd-cluster-0 --initial-advertise-peer-urls https://192.168.1.202:2380

2019-12-10 22:28:35.175032 I | mvcc: restore compact to 46505

2019-12-10 22:28:35.232386 I | etcdserver/membership: added member 12229714d8728d0e [https://192.168.1.200:2380] to cluster b8ef796b710cde7d

2019-12-10 22:28:35.232507 I | etcdserver/membership: added member 552fb05951af50c9 [https://192.168.1.203:2380] to cluster b8ef796b710cde7d

2019-12-10 22:28:35.232541 I | etcdserver/membership: added member 8b4f4a6559bf7c2c [https://192.168.1.202:2380] to cluster b8ef796b710cde7d

[root@node1 k8s1]# tree etcd2.etcd/

etcd2.etcd/

└── member

├── snap

│ ├── 0000000000000001-0000000000000003.snap

│ └── db

└── wal

└── 0000000000000000-0000000000000000.wal

[root@node1 k8s1]# cp -r etcd1.etcd/member /var/lib/etcd/

[root@node1 k8s1]# systemctl restart etcd

 

③【etcd3节点操作】

[root@node2 ~]# cd /backup/k8s1/

[root@node2 k8s1]# ETCDCTL_API=3 etcdctl snapshot restore snapshot.db --name etcd3 --initial-cluster etcd1=https://192.168.1.200:2380,etcd2=https://192.168.1.202:2380,etcd3=https://192.168.1.203:2380 --initial-cluster-token etcd-cluster-0 --initial-advertise-peer-urls https://192.168.1.203:2380

2019-12-10 22:28:55.943364 I | mvcc: restore compact to 46505

2019-12-10 22:28:55.988674 I | etcdserver/membership: added member 12229714d8728d0e [https://192.168.1.200:2380] to cluster b8ef796b710cde7d

2019-12-10 22:28:55.988726 I | etcdserver/membership: added member 552fb05951af50c9 [https://192.168.1.203:2380] to cluster b8ef796b710cde7d

2019-12-10 22:28:55.988754 I | etcdserver/membership: added member 8b4f4a6559bf7c2c [https://192.168.1.202:2380] to cluster b8ef796b710cde7d

[root@node2 k8s1]# tree etcd3.etcd/

etcd3.etcd/

└── member

├── snap

│ ├── 0000000000000001-0000000000000003.snap

│ └── db

└── wal

└── 0000000000000000-0000000000000000.wal

 

[root@node2 k8s1]# cp -r etcd1.etcd/member /var/lib/etcd/

[root@node2 k8s1]# systemctl restart etcd

 

6：在deploy节点上操作重建网络

[root@master ansible]# cd /etc/ansible/

[root@master ansible]# ansible-playbook tools/change_k8s_network.yml

 

 7：查看pod、svc恢复是否成功

[root@master ansible]# kubectl get svc

1 NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
2 kubernetes   ClusterIP   10.68.0.1       <none>        443/TCP    5d5h
3 nginx        ClusterIP   10.68.241.175   <none>        80/TCP     5d4h
4 tomcat       ClusterIP   10.68.235.35    <none>        8080/TCP   76m

[root@master ansible]# kubectl get pods

1 NAME                     READY   STATUS              RESTARTS   AGE
2 nginx-7c45b84548-4998z   1/1     Running             0          5d4h
3 tomcat-8fc9f5995-9kl5b   1/1     Running             0          77m

 

三、自动备份、自动恢复

 

1：一键备份

[root@master ansible]# ansible-playbook /etc/ansible/23.backup.yml

 

2：模拟故障

[root@master ansible]# ansible-playbook /etc/ansible/99.clean.yml

 

修改文件/etc/ansible/roles/cluster-restore/defaults/main.yml，指定要恢复的etcd快照备份，如果不修改就是最新的一次

 

3：执行自动恢复操作

[root@master ansible]# ansible-playbook /etc/ansible/24.restore.yml

[root@master ansible]# ansible-playbook /etc/ansible/tools/change_k8s_network.yml