ELK日志分析系统(4)elasticsearch数据存储

1. 概述

　　logstash把格式化的数据发送到elasticsearch以后，elasticsearch负责存储搜索日志数据

      elasticsearch的搜索接口还是很强大的，这边不详细展开，因为kibana会去调用el的接口；

　　本文将讲解elasticsearch的相关配置和遇到的问题，至于elasticsearch的相关搜索使用，后面会找个时间整理一下。

2. 配置

　　配置路径:docker-elk/elasticsearch/config/elasticsearch.yml

• 关闭安全验证，否则kibana连接不上：xpack.security.enabled:false
• 配置支持跨域调用,否则kibana会提示连接不上: http.cors.enabled: true

　　另外由于elasticsearch很容易被攻击，所以建议不要把elasticsearch的端口对外开放

cluster.name: "docker-cluster"
network.host: 0.0.0.0

## Use single node discovery in order to disable production mode and avoid bootstrap checks
## see https://www.elastic.co/guide/en/elasticsearch/reference/current/bootstrap-checks.html
#
discovery.type: single-node

## X-Pack settings
## see https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-xpack.html
#
xpack.license.self_generated.type: trial
xpack.security.enabled: false
xpack.monitoring.collection.enabled: true

http.cors.enabled: true
http.cors.allow-origin: "*"

　　elasticsearch的缓存路径是/usr/share/elasticsearch/data

　　验证是否成功：

　　访问http://192.168.1.165:9200 ,如果得到以下数据表示成功： 

 3. 异常处理

  3.1. index has exceeded [1000000] - maximum allowed to be analyzed for highlighting

　　详细的出错内容是这样：

　　　　{"type":"illegal_argument_exception","reason":"The length of [message] field of [l60ZgW0Bv9XMTlnX27A_] doc of [syslog] index has exceeded [1000000] - maximum allowed to be analyzed for highlighting. This maximum can be set by changing the [index.highlight.max_analyzed_offset] index level setting. For large texts, indexing with offsets or term vectors is recommended!”}}

 　　错误原因：索引偏移量默认是100000，超过了

　　最大迁移索引不能配置在配置文件中，只能接口修改

# 修改最大索引迁移

curl -XPUT "http://192.168.1.165:9200/_settings" -H 'Content-Type: application/json' -d' {
    "index" : {
        "highlight.max_analyzed_offset" : 100000000
    }
}’

  3.1. circuit_breaking_exception', '[parent] Data too large, data for [] would be [246901928/235.4mb], which is larger than the limit of [246546432/235.1mb]

　　详细的出错内容是这样：

　　　　elasticsearch.exceptions.TransportError: TransportError(429, 'circuit_breaking_exception', '[parent] Data too large, data for [] would be [246901928/235.4mb], which is larger than the limit of [246546432/235.1mb], real usage: [246901768/235.4mb], new bytes reserved: [160/160b], usages [request=0/0b, fielddata=11733/11.4kb, in_flight_requests=160/160b, accounting=6120593/5.8mb]')

　　错误原因：

　　　　堆内存不够当前查询加载数据所以会报 https://github.com/docker-library/elasticsearch/issues/98

 　　解决方案：

• 提高堆栈内存

　　　　在宿主机执行：sudo sysctl -w vm.max_map_count=262144

　　　　docker增加命令参数设置java的虚拟机初始化堆栈大小1G，和最大堆栈大小3G

　　　　docker-compose路径:配置路径:docker-elk/docker-compose.yml　　 

services:
  elasticsearch:
    build:
      context: elasticsearch/
      args:
        ELK_VERSION: $ELK_VERSION
    volumes:
      - type: bind
        source: ./elasticsearch/config/elasticsearch.yml
        target: /usr/share/elasticsearch/config/elasticsearch.yml
        read_only: true
      - type: volume
        source: elasticsearch
        target: /usr/share/elasticsearch/data
    ports:
      - "9200:9200"
      - "9300:9300"
    environment:
      ES_JAVA_OPTS: "-Xms1g -Xmx3g"
      ELASTIC_PASSWORD: changeme
      LOGSPOUT: ignore
    networks:
      - elk

• 增加堆内存的使用率，默认70%

curl -X PUT "http://192.168.1.165:9200/_cluster/settings" -H 'Content-Type: application/json' -d'

 {

     "transient" : {

         "indices.breaker.total.limit" : "90%"

     }

 }’

3. 安装可视化插件

　　使用docker启动

　　docker run -d --name elasticsearch-head -p 9100:9100 mobz/elasticsearch-head:5

　　elasticsearch需要配置支持跨域调用,否则会提示连接不上

　　ElasticSearch head入口：http://192.168.1.165:9100

　　插件效果如下：

　　这个插件估计对新版本的elasticsearch支持不好，后面可以换一个支持新版本elsticsearch的插件。