CentOS下ELK套件搭建日志分析和监控平台
1 .概述
ELK套件（ELK stack）是指ElasticSearch、Logstash和Kibana三件套。这三个软件可以组成一套日志分析和监控工具。
由于三个软件各自的版本号太多，建议采用ElasticSearch官网推荐的搭配组合：http://www.elasticsearch.org/overview/elkdownloads/
2 .环境准备
2.1 软件要求
本文把ELK套件部署在一台CentOS单机上。
具体的版本要求如下：
操作系统版本：CentOS 6.4；
JDK版本：1.7.0；
Logstash版本：1.4.2；
ElasticSearch版本：1.4.2；
Kibana版本：3.1.2；
2.2 防火墙配置
为了正常使用HTTP服务等，需要关闭防火墙：
# service iptables stop
# service iptables stop
或者可以不关闭防火墙，但是要在iptables中打开相关的端口：
# vim /etc/sysconfig/iptables
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 9200 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 9292 -j ACCEPT
# service iptables restart
# vim /etc/sysconfig/iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT -A INPUT -m state --state NEW -m tcp -p tcp --dport 9200 -j ACCEPT -A INPUT -m state --state NEW -m tcp -p tcp --dport 9292 -j ACCEPT # service iptables restart
3.安装JDK
ElasticSearch和Logstash依赖于JDK，所以需要安装JDK：
# yum -y install java-1.7.0-openjdk*
# java -version
# yum -y install java-1.7.0-openjdk* # java -version
4. 安装ElasticSearch
ElasticSearch默认的对外服务的HTTP端口是9200，节点间交互的TCP端口是9300。
下载ElasticSearch：
# mkdir -p /opt/software && cd /opt/software
# sudo wget https://download.elasticsearch.org/elasticsearch/elasticsearch/elasticsearch-1.4.2.tar.gz
# sudo tar -zxvf elasticsearch-1.4.2.tar.gz -C /usr/local/
# ln -s /usr/local/elasticsearch-1.4.2 /usr/local/elasticsearch
# mkdir -p /opt/software && cd /opt/software # sudo wget https://download.elasticsearch.org/elasticsearch/elasticsearch/elasticsearch-1.4.2.tar.gz # sudo tar -zxvf elasticsearch-1.4.2.tar.gz -C /usr/local/ # ln -s /usr/local/elasticsearch-1.4.2 /usr/local/elasticsearch
安装elasticsearch-servicewrapper，并启动ElasticSearch服务：
# sudo wget https://github.com/elasticsearch/elasticsearch-servicewrapper/archive/master.tar.gz
# sudo tar -zxvf master
# mv /opt/software/elasticsearch-servicewrapper-master/service /usr/local/elasticsearch/bin/
# /usr/local/elasticsearch/bin/service/elasticsearch start
# sudo wget https://github.com/elasticsearch/elasticsearch-servicewrapper/archive/master.tar.gz # sudo tar -zxvf master # mv /opt/software/elasticsearch-servicewrapper-master/service /usr/local/elasticsearch/bin/ # /usr/local/elasticsearch/bin/service/elasticsearch start
测试ElasticSearch服务是否正常，预期返回200的状态码：
# curl -X GET http://localhost:9200
# curl -X GET http://localhost:9200
5.安装Logstash
Logstash默认的对外服务的端口是9292
下载Logstash：
# sudo wget https://download.elasticsearch.org/logstash/logstash/logstash-1.4.2.tar.gz
# sudo tar -zxvf logstash-1.4.2.tar.gz -C /usr/local/
# ln -s /usr/local/logstash-1.4.2 /usr/local/logstash
# sudo wget https://download.elasticsearch.org/logstash/logstash/logstash-1.4.2.tar.gz # sudo tar -zxvf logstash-1.4.2.tar.gz -C /usr/local/ # ln -s /usr/local/logstash-1.4.2 /usr/local/logstash
简单测试Logstash服务是否正常，预期可以将输入内容以简单的日志形式打印在界面上：
# /usr/local/logstash/bin/logstash -e 'input { stdin { } } output { stdout {} }'
# /usr/local/logstash/bin/logstash -e 'input { stdin { } } output { stdout {} }'
创建Logstash配置文件，并再次测试Logstash服务是否正常，预期可以将输入内容以结构化的日志形式打印在界面上：
# mkdir -p /usr/local/logstash/etc
# vim /usr/local/logstash/etc/hello_search.conf
input {
stdin {
type => "human"
}
}
output {
stdout {
codec => rubydebug
}
elasticsearch {
host => "10.111.121.22"
port => 9300
}
}
# /usr/local/logstash/bin/logstash -f /usr/local/logstash/etc/hello_search.conf
# mkdir -p /usr/local/logstash/etc
# vim /usr/local/logstash/etc/hello_search.conf
input {
stdin {
type => "human"
}
}
output {
stdout {
codec => rubydebug
}
elasticsearch {
host => "10.111.121.22"
port => 9300
}
}
# /usr/local/logstash/bin/logstash -f /usr/local/logstash/etc/hello_search.conf
6.安装Kibana
CentOS默认预装了Apache，所以将Kibana的代码直接拷贝到Apache可以访问的目录下即可
# sudo wget https://download.elasticsearch.org/kibana/kibana/kibana-3.1.2.tar.gz
# sudo tar -zxvf kibana-3.1.2.tar.gz
# mv kibana-3.1.2 /var/www/html/kibana
# sudo wget https://download.elasticsearch.org/kibana/kibana/kibana-3.1.2.tar.gz # sudo tar -zxvf kibana-3.1.2.tar.gz # mv kibana-3.1.2 /var/www/html/kibana
修改Kibana的配置文件，把elasticsearch所在行的内容替换成如下：
# vim /var/www/html/kibana/config.js
elasticsearch: "http://10.111.121.22:9200",
# vim /var/www/html/kibana/config.js elasticsearch: "http://10.111.121.22:9200",
启动一下HTTP服务：
# service httpd start
# service httpd start
修改ElasticSearch的配置文件，追加一行内容，并重启ElasticSearch服务：
# vim /usr/local/elasticsearch/config/elasticsearch.yml
http.cors.enabled: true
# /usr/local/elasticsearch/bin/service/elasticsearch restart
# vim /usr/local/elasticsearch/config/elasticsearch.yml http.cors.enabled: true # /usr/local/elasticsearch/bin/service/elasticsearch restart
然后就可以通过浏览器访问Kibana了：
http://10.111.121.22/kibana
http://10.111.121.22/kibana
现在，在之前的Logstash会话中输入任意字符，就可以在Kibana中查看到日志情况。
7. 配置Logstash
再次创建Logstash配置文件，这里将HTTP日志和文件系统日志作为输入，输出直接传给ElasticSearch，不再打印在界面上：
# vim /usr/local/logstash/etc/logstash_agent.conf
input {
file {
type => "http.access"
path => ["/var/log/httpd/access_log"]
}
file {
type => "http.error"
path => ["/var/log/httpd/error_log"]
}
file {
type => "messages"
path => ["/var/log/messages"]
}
}
output {
elasticsearch {
host => "10.111.121.22"
port => 9300
}
}
# nohup /usr/local/logstash/bin/logstash -f /usr/local/logstash/etc/logstash_agent.conf &
# vim /usr/local/logstash/etc/logstash_agent.conf
input {
file {
type => "http.access"
path => ["/var/log/httpd/access_log"]
}
file {
type => "http.error"
path => ["/var/log/httpd/error_log"]
}
file {
type => "messages"
path => ["/var/log/messages"]
}
}
output {
elasticsearch {
host => "10.111.121.22"
port => 9300
}
}
# nohup /usr/local/logstash/bin/logstash -f /usr/local/logstash/etc/logstash_agent.conf &