1.官网提供snap快照备份恢复

https://www.elastic.co/guide/en/elasticsearch/reference/7.9/snapshot-restore.html

环境要求

要求所有es节点，挂载同一个共享目录，可以使用NFS。

注意背景

[root@devops01 ~]#id elasticsearch

uid=998(elasticsearch) gid=996(elasticsearch) groups=996(elasticsearch)

[root@devops01 ~]#

搭建NFS机器，服务端

yum install nfs-utils -y

# 根据es的用户信息，创建挂载用户

groupadd elasticsearch -g 996

useradd elasticsearch -g 996 -u 998 -M -s /sbin/nologin

cat > /etc/exports << 'EOF'

/es-nfs-data 10.0.0.0/24(rw,sync,all_squash,anonuid=998,anongid=996)

EOF

# 目录创建授权

[root yc-k8s ~]#mkdir -p /es-nfs-data

[root yc-k8s ~]#chown -R elasticsearch.elasticsearch /es-nfs-data/

[root yc-k8s ~]#ll -d  /es-nfs-data/

drwxr-xr-x. 2 elasticsearch elasticsearch 6 Dec  3 02:16 /es-nfs-data/

[root yc-k8s ~]#

[root yc-k8s ~]#systemctl restart nfs

[root yc-k8s ~]#showmount -e 10.0.0.122

Export list for 10.0.0.122:

/es-nfs-data 10.0.0.0/24

es节点安装nfs插件

cat > nfs-client.sh <<'EOF'

yum install nfs-utils -y

mkdir /es-client-data -p

mount -t nfs 10.0.0.122:/es-nfs-data  /es-client-data

EOF

sh nfs-client.sh

# 检查挂载

df -h |grep es-client-data

es节点修改config，开启snapshot

每个节点config.yml添加配置

path.repo: /es-client-data/

# 如

[es-node3 root ~]#cat /etc/elasticsearch/elasticsearch.yml

cluster.name: yuchao_es

node.name: es-node3

path.data: /var/lib/elasticsearch/

path.logs: /var/log/elasticsearch/

bootstrap.memory_lock: true

network.host: 127.0.0.1,10.0.0.20

http.port: 9200

discovery.seed_hosts: ["10.0.0.18","10.0.0.19","10.0.0.20"]

cluster.initial_master_nodes: ["10.0.0.18"]

path.repo: /es-client-data/

[es-node3 root ~]#

# 重启

systemctl restart elasticsearch.service

确保重启正确

1.先注册快照仓库

PUT /_snapshot/my_backup

{

  "type": "fs",

  "settings": {

    "location": "/es-client-data/my_backup_location",

    "compress": true

  }

}

# 可以查询仓库信息

GET /_snapshot/my_backup

2.创建一个快照

PUT /_snapshot/my_backup/snapshot_1?wait_for_completion=true

检查快照

图解nfs快照

3.针对具体index的快照

# 创建第二个快照，名字snapshot_2 

PUT /_snapshot/my_backup/snapshot_2?wait_for_completion=true

{

  "indices": "t1,t2",

  "ignore_unavailable": true,

  "include_global_state": false

  }

}

4.查看快照信息



GET /_snapshot

GET /_snapshot/my_backup/

GET /_snapshot/my_backup/snapshot_1

GET /_snapshot/my_backup/snapshot_2

5.查看正在运行的快照

GET /_snapshot/my_backup/_current

{

  "snapshots" : [ ]

}

6.演练恢复索引

1. 删除 t2库

2.基于有该t2 库的快照

POST /_snapshot/my_backup/snapshot_2/_restore

3.默认恢复，发现有同名index，导致恢复错误

4.可以单独还原某个index，或者删除es数据，全库恢复。

GET /_snapshot

GET /_snapshot/my_backup/

GET /_snapshot/my_backup/snapshot_1

GET /_snapshot/my_backup/snapshot_2

GET /_snapshot/my_backup/_current

POST /_snapshot/my_backup/snapshot_2/_restore

# 恢复指定的索引

POST /_snapshot/my_backup/snapshot_2/_restore

{

  "indices": "t2",

  "ignore_unavailable": true,

  "include_global_state": false,

  "rename_pattern": "index_(.+)",

  "rename_replacement": "restored_index_$1",

  "include_aliases": false

}

# 参数解释

上面的indices, 表示只恢复索引’index_1’

rename_pattern: 表示重命名索引以’index_’开头的索引.（注意我们这里索引叫做t2，所以没作用）

rename_replacement: 表示将所有的索引重命名为’restored_index_xxx’.如index_1会被重命名为restored_index_1.

指定index恢复

恢复且修改index名



# 如果想修改恢复后的index名字

POST /_snapshot/my_backup/snapshot_2/_restore

{

  "indices": "t2",

  "ignore_unavailable": true,

  "include_global_state": false,

  "rename_pattern": "t(.+)",

  "rename_replacement": "restored_index_$1",

  "include_aliases": false

}

7.用日期命名快照

不建议去用。

PUT /_snapshot/my_backup/<snapshot-{now/d}>

PUT /_snapshot/my_backup/%3Csnapshot-%7Bnow%2Fd%7D%3E

8.记录es练习接口

PUT /_snapshot/my_backup

{

  "type": "fs",

  "settings": {

    "location": "/es-client-data/my_backup_location",

    "compress": true

  }

}

GET /_snapshot/my_backup

PUT /_snapshot/my_backup/snapshot_1?wait_for_completion=true

PUT /_snapshot/my_backup/snapshot_2?wait_for_completion=true

{

  "indices": "t1,t2",

  "ignore_unavailable": true,

  "include_global_state": false

  }

}

GET /_snapshot/

GET /_snapshot/my_backup/

GET /_snapshot/my_backup/_all

GET /_snapshot/my_backup/snapshot_1

GET /_snapshot/my_backup/snapshot_2

GET /_snapshot/my_backup/_current

POST /_snapshot/my_backup/snapshot_2/_restore

POST /_snapshot/my_backup/snapshot_2/_restore

{

  "indices": "t2",

  "ignore_unavailable": true,

  "include_global_state": false,

  "rename_pattern": "index_(.+)",

  "rename_replacement": "restored_index_$1",

  "include_aliases": false

}

POST /_snapshot/my_backup/snapshot_2/_restore

{

  "indices": "t2",

  "ignore_unavailable": true,

  "include_global_state": false,

  "rename_pattern": "t(.+)",

  "rename_replacement": "restored_index_$1",

  "include_aliases": false

}

PUT /_snapshot/my_backup/%3Csnapshot-%7Bnow%2Fd%7D%3E

2.第三方备份工具

1.安装node环境，基于nodejs开发的备份工具

# 注意node版本要求和于超老师一致

2.软件官网

https://www.npmjs.com/package/elasticdump

2.1 安装node

wget https://nodejs.org/dist/v10.16.3/node-v10.16.3-linux-x64.tar.xz

tar -xf node-v10.16.3-linux-x64.tar.xz 

[root yc-k8s /opt]#

[root yc-k8s /opt]#ln -s node-v10.16.3-linux-x64/ node

[root yc-k8s /opt]#

[root yc-k8s /opt]#echo 'export PATH=/opt/node/bin:$PATH' >> /etc/profile

[root yc-k8s /opt]#

[root yc-k8s /opt]#source /etc/profile

[root yc-k8s /opt]#

[root yc-k8s /opt]#node -v

v10.16.3

[root yc-k8s /opt]#

[root yc-k8s /opt]#npm -v

6.9.0

[root yc-k8s /opt]#

# 设置淘宝源

# 于超老师这里测试，腾讯源快一点

npm config set registry https://registry.npm.taobao.org

npm config set registry http://mirrors.cloud.tencent.com/npm/

npm config get registry

# 安装elasticdump备份工具

[root yc-k8s /opt]#npm install elasticdump -g

[root yc-k8s /opt]#elasticdump --version

6.94.1

2.2 备份命令

备份es数据为可读的json文件



[root yc-k8s /opt]#elasticdump \

> --input=http://10.0.0.18:9200/t1 \

> --output=/es-nfs-data/t1.json \

> --type=data

Sat, 03 Dec 2022 14:35:45 GMT | starting dump

Sat, 03 Dec 2022 14:35:45 GMT | got 8 objects from source elasticsearch (offset: 0)

Sat, 03 Dec 2022 14:35:45 GMT | sent 8 objects to destination file, wrote 8

Sat, 03 Dec 2022 14:35:45 GMT | got 0 objects from source elasticsearch (offset: 8)

Sat, 03 Dec 2022 14:35:45 GMT | Total Writes: 8

Sat, 03 Dec 2022 14:35:45 GMT | dump complete

[root yc-k8s /opt]#

[root yc-k8s /es-nfs-data]#cat t1.json

{"_index":"t1","_type":"_doc","_id":"7HNg1IQBRcFJVNOeWVxR","_score":1,"_source":{"name":"yu1","age":"28","address":"JS","job":"dev"}}

{"_index":"t1","_type":"_doc","_id":"7XNg1IQBRcFJVNOeWVyL","_score":1,"_source":{"name":"yu2","age":"27","address":"BJ","job":"dev"}}

{"_index":"t1","_type":"_doc","_id":"7nNg1IQBRcFJVNOeWVyd","_score":1,"_source":{"name":"yu3","age":"26","address":"SD","job":"ops"}}

{"_index":"t1","_type":"_doc","_id":"73Ng1IQBRcFJVNOeWVyq","_score":1,"_source":{"name":"yu4","age":"25","address":"JX","job":"ops"}}

{"_index":"t1","_type":"_doc","_id":"8HNg1IQBRcFJVNOeWVy5","_score":1,"_source":{"name":"jack01","age":"19","address":"YN","job":"test"}}

{"_index":"t1","_type":"_doc","_id":"8XNg1IQBRcFJVNOeWVzD","_score":1,"_source":{"name":"tom02","age":"30","address":"DB","job":"test"}}

{"_index":"t1","_type":"_doc","_id":"8nNg1IQBRcFJVNOeWVzN","_score":1,"_source":{"name":"david03","age":"30","address":"BJ","job":"test"}}

{"_index":"t1","_type":"_doc","_id":"83Ng1IQBRcFJVNOeWVzY","_score":1,"_source":{"name":"xiaohei01","age":"17","address":"BJ","job":"ops"}}

[root yc-k8s /es-nfs-data]#

备份且压缩

elasticdump \

--input=http://10.0.0.18:9200/t2 \

--output=$ \

  | gzip > /es-nfs-data/t2.json.gz

[root yc-k8s /es-nfs-data]#gzip -d t2.json.gz

[root yc-k8s /es-nfs-data]#ll

total 12

drwxr-xr-x. 3 elasticsearch elasticsearch 4096 Dec  3 04:50 my_backup_location

-rw-r--r--. 1 root          root          1090 Dec  3 22:35 t1.json

-rw-r--r--. 1 root          root           402 Dec  3 22:37 t2.json

[root yc-k8s /es-nfs-data]#cat t2.json

{"_index":"t2","_type":"_doc","_id":"9HNg1IQBRcFJVNOe-1xE","_score":1,"_source":{"name":"yu1","age":"28","address":"JS","job":"dev"}}

{"_index":"t2","_type":"_doc","_id":"9XNg1IQBRcFJVNOe-1yA","_score":1,"_source":{"name":"yu2","age":"27","address":"BJ","job":"dev"}}

{"_index":"t2","_type":"_doc","_id":"9nNg1IQBRcFJVNOe-1yS","_score":1,"_source":{"name":"yu3","age":"26","address":"SD","job":"ops"}}

[root yc-k8s /es-nfs-data]#

2.3 恢复数据

# 恢复数据，就是input，output反过来

[root yc-k8s /es-nfs-data]#elasticdump \

>  --input=/es-nfs-data/t2.json \

>  --output=http://10.0.0.18:9200/t2

Sat, 03 Dec 2022 14:44:23 GMT | starting dump

Sat, 03 Dec 2022 14:44:23 GMT | got 3 objects from source file (offset: 0)

Sat, 03 Dec 2022 14:44:23 GMT | sent 3 objects to destination elasticsearch, wrote 3

Sat, 03 Dec 2022 14:44:23 GMT | got 0 objects from source file (offset: 3)

Sat, 03 Dec 2022 14:44:23 GMT | Total Writes: 3

Sat, 03 Dec 2022 14:44:23 GMT | dump complete

[root yc-k8s /es-nfs-data]#

2.4 批量备份

# 去掉以点开头的index

curl -s 10.0.0.18:9200/_cat/indices | awk '{print $3}' | grep -v '^\.'

# 脚本

#!/bin/bash

# author : www.yuchaoit.cn

indexs=$(curl -s 10.0.0.18:9200/_cat/indices | awk '{print $3}' | grep -v '^\.')

for i in $indexs

do

    elasticdump \

    --input=http://10.0.0.18:9200/${i} \

    --output=/es-nfs-data/${i}.json \

    --type=data

done

备份结果

root yc-k8s /es-nfs-data]#

[root yc-k8s /es-nfs-data]#sh for-index.sh

Sat, 03 Dec 2022 14:54:57 GMT | starting dump

Sat, 03 Dec 2022 14:54:57 GMT | got 3 objects from source elasticsearch (offset: 0)

Sat, 03 Dec 2022 14:54:57 GMT | sent 3 objects to destination file, wrote 3

Sat, 03 Dec 2022 14:54:57 GMT | got 0 objects from source elasticsearch (offset: 3)

Sat, 03 Dec 2022 14:54:57 GMT | Total Writes: 3

Sat, 03 Dec 2022 14:54:57 GMT | dump complete

Sat, 03 Dec 2022 14:54:57 GMT | starting dump

Sat, 03 Dec 2022 14:54:57 GMT | got 8 objects from source elasticsearch (offset: 0)

Sat, 03 Dec 2022 14:54:57 GMT | sent 8 objects to destination file, wrote 8

Sat, 03 Dec 2022 14:54:57 GMT | got 0 objects from source elasticsearch (offset: 8)

Sat, 03 Dec 2022 14:54:57 GMT | Total Writes: 8

Sat, 03 Dec 2022 14:54:57 GMT | dump complete

Sat, 03 Dec 2022 14:54:57 GMT | starting dump

Sat, 03 Dec 2022 14:54:57 GMT | got 3 objects from source elasticsearch (offset: 0)

Sat, 03 Dec 2022 14:54:57 GMT | sent 3 objects to destination file, wrote 3

Sat, 03 Dec 2022 14:54:57 GMT | got 0 objects from source elasticsearch (offset: 3)

Sat, 03 Dec 2022 14:54:57 GMT | Total Writes: 3

Sat, 03 Dec 2022 14:54:57 GMT | dump complete

[root yc-k8s /es-nfs-data]#ll

\total 20

-rw-r--r--. 1 root          root           248 Dec  3 22:54 for-index.sh

drwxr-xr-x. 3 elasticsearch elasticsearch 4096 Dec  3 04:50 my_backup_location

-rw-r--r--. 1 root          root           444 Dec  3 22:54 restored_index_2.json

-rw-r--r--. 1 root          root          1090 Dec  3 22:54 t1.json

-rw-r--r--. 1 root          root           402 Dec  3 22:54 t2.json

[root yc-k8s /es-nfs-data]#

2.5 密码认证

es有密码时，备份命令

    elasticdump \

    --input=http://name:password@10.0.0.18:9200/t2 \

    --output=/es-nfs-data/t2.json \

    --type=data

2.6 建议用法

1. 想分析es数据，用elasticdump导出json

2. 仅仅备份数据，用es官网工具

3. 恢复es数据，如果数据冲突会被覆盖

3.es安全认证

逻辑图

官网资料

https://www.elastic.co/guide/en/elasticsearch/reference/current/configuring-stack-security.html

1.创建证书

1. 创建证书，输入密码

[root@es-node1 ~]#

[root@es-node1 ~]#

[root@es-node1 ~]#/usr/share/elasticsearch/bin/elasticsearch-certutil ca

This tool assists you in the generation of X.509 certificates and certificate

signing requests for use with SSL/TLS in the Elastic stack.

The 'ca' mode generates a new 'certificate authority'

This will create a new X.509 certificate and private key that can be used

to sign certificate when running in 'cert' mode.

Use the 'ca-dn' option if you wish to configure the 'distinguished name'

of the certificate authority

By default the 'ca' mode produces a single PKCS#12 output file which holds:

    * The CA certificate

    * The CA's private key

If you elect to generate PEM format certificates (the -pem option), then the output will

be a zip file containing individual files for the CA certificate and private key

Please enter the desired output file [elastic-stack-ca.p12]:

Enter password for elastic-stack-ca.p12 :

[root@es-node1 ~]#

[root@es-node1 ~]#

[root@es-node1 ~]#

[root@es-node1 ~]#file /usr/share/elasticsearch/elastic-stack-ca.p12

/usr/share/elasticsearch/elastic-stack-ca.p12: data

2.根据ca整数，创建私钥，也可以二次设置密码

/usr/share/elasticsearch/bin/elasticsearch-certutil cert --ca elastic-stack-ca.p12

3.检查

[root@es-node1 /usr/share/elasticsearch]#ll

total 576

drwxr-xr-x  2 root root   4096 Nov 18 23:53 bin

-rw-------  1 root root   3443 Dec  3 23:10 elastic-certificates.p12

-rw-------  1 root root   2527 Dec  3 23:08 elastic-stack-ca.p12

drwxr-xr-x  9 root root    107 Nov 18 23:53 jdk

drwxr-xr-x  3 root root   4096 Nov 18 23:53 lib

-rw-r--r--  1 root root  13675 Sep  2  2020 LICENSE.txt

drwxr-xr-x 52 root root   4096 Nov 18 23:53 modules

-rw-rw-r--  1 root root 544318 Sep  2  2020 NOTICE.txt

drwxr-xr-x  2 root root      6 Sep  2  2020 plugins

-rw-r--r--  1 root root   7007 Sep  2  2020 README.asciidoc

4.复制证书到固定位置，同步es节点

[root@es-node1 /usr/share/elasticsearch]#scp -r /etc/elasticsearch/certs root@10.0.0.19:/etc/elasticsearch/

elastic-certificates.p12                                                                                                                                                                                    100% 3443     5.1MB/s   00:00

elastic-stack-ca.p12                                                                                                                                                                                        100% 2527     3.1MB/s   00:00

[root@es-node1 /usr/share/elasticsearch]#scp -r /etc/elasticsearch/certs root@10.0.0.20:/etc/elasticsearch/

elastic-certificates.p12                                                                                                                                                                                    100% 3443     5.3MB/s   00:00

elastic-stack-ca.p12                                                                                                                                                                                        100% 2527     2.8MB/s   00:00

[root@es-node1 /usr/share/elasticsearch]#

5.修改es节点配置文件，开启安全功能

# es安全组件，xpack，开启即可。

# 来自于官网的教程，复制粘贴即可，有机会再阅读es数据，逐步深入学习。

xpack.security.enabled: true

xpack.security.transport.ssl.enabled: true

xpack.security.transport.ssl.verification_mode: certificate

xpack.security.transport.ssl.keystore.path: certs/elastic-stack-ca.p12

xpack.security.transport.ssl.truststore.path: certs/elastic-stack-ca.p12

6.注意修改es目录权限，重启进程

chown -R elasticsearch.elasticsearch /etc/elasticsearch/

systemctl restart elasticsearch.service 

7.检查es状态

netstat -tunlp|grep 9200

此时就已连不上了，需要账密了

创建账户，密码

默认会给一些列的内置用户，创建密码，统一123123

[root@es-node1 ~]#/usr/share/elasticsearch/bin/elasticsearch-setup-passwords interactive

Initiating the setup of passwords for reserved users elastic,apm_system,kibana,kibana_system,logstash_system,beats_system,remote_monitoring_user.

You will be prompted to enter passwords as the process progresses.

Please confirm that you would like to continue [y/N]y

Enter password for [elastic]:

passwords must be at least [6] characters long

Try again.

Enter password for [elastic]:

Reenter password for [elastic]:

Enter password for [apm_system]:

Reenter password for [apm_system]:

Enter password for [kibana_system]:

Reenter password for [kibana_system]:

Enter password for [logstash_system]:

Reenter password for [logstash_system]:

Enter password for [beats_system]:

Reenter password for [beats_system]:

Enter password for [remote_monitoring_user]:

Reenter password for [remote_monitoring_user]:

Changed password for user [apm_system]

Changed password for user [kibana_system]

Changed password for user [kibana]

Changed password for user [logstash_system]

Changed password for user [beats_system]

Changed password for user [remote_monitoring_user]

Changed password for user [elastic]

内置角色解释

账户elastic为elasticsearch超级管理员，拥有所有权限

账户kibana用于kibana组件获取相关信息用于web展示

账户logstash_system用于logstash服务获取elasticsearch的监控数据

账户beats_system用于存储es监控信息时用

账户kibana_system，用于kibana安全与es集群通讯用。

es官网，内置角色

https://www.elastic.co/guide/en/elasticsearch/reference/7.9/built-in-roles.html

2.创建kibana登录用户

务必注意，这里kibana使用刚才es创建的 账户，密码，来连接es集群。

密码保证一致，否则kibana，无法和es通信了。

[root@es-node1 ~]#vim /etc/kibana/kibana.yml 

 42 # If your Elasticsearch is protected with basic authentication, these settings provide

 43 # the username and password that the Kibana server uses to perform maintenance on the Kibana

 44 # index at startup. Your Kibana users still need to authenticate with Elasticsearch, which

 45 # is proxied through the Kibana server.

 46 elasticsearch.username: "kibana_system"

 47 elasticsearch.password: "123123"

重启kibana

[root@es-node1 ~]#systemctl restart kibana

kibana正确安全连接es

elastic

123123

普通用户kibana 123123 也可以登录

es-head登录认证

3.创建用户

kibana先创建es的索引

便于查询数据。

kibana功能space

需求：1.限制开发小于，登录kibana，只能使用某个功能，如discover,且只能看t2 索引

实践：

1. 创建space ，dev，允许只能看某些内容

创建roles

创建用户，开发小于，绑定dev角色

yu

yu123123

开发小于登录kibana

只能访问t1 index数据

4.角色访问index区别

 

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