elastalert--基于elasticsearch层面的监控和邮件报警

在做好ELK环境部署下

elastalert读取指定elasticsearch索引,根据规则匹配,如果匹配到就发邮件报警
1，安装python3
elastalert是基于Python3版本的

[root@localhost ~] yum -y install wget openssl openssl-devel gcc gcc-c++ #安装依赖
[root@localhost ~] wget -c https://www.python.org/ftp/python/3.6.2/Python-3.6.2.tgz #下载Python3
[root@localhost ~] tar -zxf Python-3.6.2.tgz #解压
[root@localhost ~] cd Python-3.6.2
[root@localhost Python-3.6.2] ./configure --prefix=/usr/local/python --with-openssl 检测环境
[root@localhost Python-3.6.2] make && make install #编译 安装

2，设置python，授权yum，并做软链接

[root@localhost ~] which python
/usr/bin/python
[root@localhost ~] rm -rf /usr/bin/python
[root@localhost ~] vim /usr/bin/yum
[root@localhost ~] cat /usr/bin/yum|sed -n '1p'
#!/usr/bin/python2
[root@localhost ~] vim /usr/libexec/urlgrabber-ext-down 
[root@localhost ~] cat /usr/libexec/urlgrabber-ext-down |sed -n '1p'
#! /usr/bin/python2
[root@localhost ~] ln -s /usr/local/python/bin/python3 /usr/bin/python
[root@localhost ~] ln -s /usr/local/python/bin/pip3 /usr/bin/pip
#做好以上操作可以执行yum了

3，安装 elastalert

[root@localhost ~] tar -zxf v0.2.1_elasticalert.tar.gz
[root@localhost ~] mv elastalert-0.2.1 /usr/local/elastalert #转移至/usr/local下

[root@localhost ~] cd /usr/local/elastalert/
[root@localhost elastalert] pip install "elasticsearch<7,>6"

[root@localhost elastalert] pip install --upgrade pip

[root@localhost elastalert] pip install -r requirements.txt

[root@localhost elastalert] python setup.py install

安装之后会自带三个命令
（1）elastalert-create-index：ElastAlert会把执行记录存放到一个ES 索引中，该命令就是用来 创建这个索引的，默认情况下，索引名叫elastalert_status。其中有4个 _type，都有 自己的@timestamp字段，所以同样也可以用kibana，来查看这个索引的日志记录情况。
（2）elastalert-rule-from-kibana：从Kibana3已保存的仪表盘中读取Filtering设置，帮助生成config.yaml里的配置。不过注意，它只会读取filtering，不包括queries。
（3）elastalert-test-rule：测试自定义配置中的rule设置。

4，设置elastalert索引

[root@localhost elastalert] cd /usr/local/python/bin/
[root@localhost bin] ./elastalert-create-index 

Enter Elasticsearch host: 192.168.59.110 #elasticsearch主机ip

Enter Elasticsearch port: 9200 #elasticsearch端口号
Use SSL? t/f: f #否

Enter optional basic-auth username (or leave blank): #回车

Enter optional basic-auth password (or leave blank): #回车

Enter optional Elasticsearch URL prefix (prepends a string to the URL of every request): #回车

New index name? (Default elastalert_status) #回车

New alias name? (Default elastalert_alerts) #回车

Name of existing index to copy? (Default None)  #回车

Elastic Version: 6.6.2
Reading Elastic 6 index mappings:
Reading index mapping 'es_mappings/6/silence.json'
Reading index mapping 'es_mappings/6/elastalert_status.json'
Reading index mapping 'es_mappings/6/elastalert.json'
Reading index mapping 'es_mappings/6/past_elastalert.json'
Reading index mapping 'es_mappings/6/elastalert_error.json'
New index elastalert_status created
Done!

5，修改配置文件

[root@localhost bin] cd /usr/local/elastalert/
[root@localhost elastalert] mv config.yaml.example config.yaml #重命名
[root@localhost elastalert] vim config.yaml 
[root@localhost elastalert] cat config.yaml |grep -v "^#"|sed '/^$/d'

rules_folder: example_rules # 用来加载rule的目录，默认是example_rules
run_every: # 用来设置定时向elasticsearch发送请求，也就是告警执行的频率
  minutes: 1
buffer_time: # 用来设置请求里时间字段的范围
  minutes: 15
es_host: 192.168.59.110
es_port: 9200
writeback_index: elastalert_status# elastalert产生的日志在elasticsearch中的创建的索引
writeback_alias: elastalert_alerts
alert_time_limit: # 失败重试的时间限制
  days: 2

6，设置规则，配置邮件报警

[root@localhost elastalert] cd example_rules/
[root@localhost example_rules] vim example_frequency.yaml 
[root@localhost example_rules] mv example_frequency.yaml nginx_frequency.yaml  #重命名
[root@localhost example_rules] cat nginx_frequency.yaml |grep -v "^#"|sed '/^$/d'

es_host: 192.168.59.110
es_port: 9200
name: nginx rule #规则名字必须是唯一的
type: frequency
index: nginx_log-* # 监控的索引
num_events: 5 # 限定时间内，发生的次数
timeframe:
  hours: 1 # 一小时内有5个错误日志写进ES的话就发送邮件
filter:
- term: #以正则的方式匹配， “404” 就是已有日志写进es就算
    status: "404"
alert:
- "email"
email:
- "[email protected]"
smtp_host: smtp.qq.com
smtp_port: 25
smtp_auth_file: /usr/local/elastalert/example_rules/email_auth.yaml
from_addr: [email protected]

[root@localhost example_rules] vim email_auth.yaml
[root@localhost example_rules] cat email_auth.yaml 
user: "[email protected]" 
password: "zxvbnnggjfgd" #这里是授权码

7，启动elastalert，实时监控nginx日志

[root@localhost example_rules] cd ..
[root@localhost elastalert] /usr/local/python/bin/elastalert --config /usr/local/elastalert/config.yaml --rule /usr/local/elastalert/example_rules/nginx_frequency.yaml --verbose

INFO:elastalert:Starting up
INFO:elastalert:Disabled rules are: []
INFO:elastalert:Sleeping for 59.999896 seconds
INFO:elastalert:Queried rule nginx rule from 2020-04-06 21:42 CST to 2020-04-06 21:57 CST: 0 / 0 hits
......
......
......
#会实时监控nginx日志，如果出现问题会以邮件方式报警