通过日志我们可以及时发现软件所遇到的问题，但是日志位于服务器上，不便于观察，可视化的实时收集日志并分析十分重要，而ELK栈为另外们提供了很好的解决方案。这里，我们使用Logstash收集Nginx日志，并输出到Elasticsearch，用Kibana来显示。
依赖
下载与配置
1. 下载与解压ELK
cd /usr/local/src/
wget -c https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.1.1.zip
wget -c https://artifacts.elastic.co/downloads/kibana/kibana-6.1.1-linux-x86_64.tar.gz
wget -c https://artifacts.elastic.co/downloads/logstash/logstash-6.1.1.tar.gz
tar -xf kibana-6.1.1-linux-x86_64.tar.gz -C /usr/local/src/
tar -xf logstash-6.1.1.tar.gz -C /usr/local/src/
unzip elasticsearch-6.1.1.zip -d /usr/local/src/
### 创建软连接
ln -sv /usr/local/src/logstash-6.1.1 /usr/local/logstash
ln -sv /usr/local/src/kibana-6.1.1-linux-x86_64/ /usr/local/kibana
ln -sv /usr/local/src/elasticsearch-6.1.1/ /usr/local/elasticsearch
vim /etc/profile.d/els.sh
# 内容如下
PATH=$PATH:/usr/local/elasticsearch/bin/
PATH=$PATH:/usr/local/kibana/bin/
PATH=$PATH:/usr/local/logstash/bin/
#
source /etc/profile.d/els.sh
2. 配置elasticsearch需要的系统配置
ulimit -n 65536
vim /etc/security/limits.conf
#limits.conf内容如下
* soft nofile 65536
* hard nofile 65536
- ELK安装X-pack扩展(可选)
logstash-plugin install x-pack
elasticsearch-plugin install -xpack
kibana-plugin install x-pack
设置ELK栈的密码
/usr/local/elasticsearch/bin/x-pack/setup-passwords interactive
4. 配置nginx的日志格式与日志路径
log_format main '{"@timestamp":"$time_iso8601",'
'"host":"$server_addr",'
' "clientip" : "$remote_addr",'
' "size" : "$body_bytes_sent" ,'
'"respnsetime":"$request_time",'
'"upstremtime":"$upstream_response_time",'
'"upstremhost":"$upstream_addr",'
'"httphost":"$host",'
'"referer":"$http_referer",'
'"xff":"$http_x_forwarded_for",'
'"agent":"$http_user_agent",'
'"clientip":"$remote_addr",'
'"request":"$request",'
'"uri":"$uri",'
'"status":"$status"}';
access_log /var/logs/nginx/access.log main;
error_log /var/logs/nginx/error.log error;
5 . 写Logstash的日志收集文件
input {
file {
type => "nginx-error-log"
path => "/usr/local/openresty/nginx/logs/error.log"
}
file {
type => "nginx-access-log"
path => "/usr/local/openresty/nginx/logs/access.log"
codec => json
}
}
filter {
if [type] =~ "nginx-error-log"
{
grok {
match => {
"message" => "(?<datetime>\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2}) \[(?<errtype>\w+)\] \S+: \*\d+ (?<errmsg>[^,]+), (?<errinfo>.*$)"
}
}
mutate {
rename => {
"message" => "z_message"
"host" => "fromhost"
}
}
} else if [type] =~ "nginx-access-log" {
mutate {
split => {"upstremtime" => ","}
}
mutate {
convert => { "upstremtime" => "float"}
}
}
if [errinfo]
{
ruby {
code => "
new_event = LogStash::Event.new(Hash[event.get('errinfo').split(', ').map{ |l| l.split(': ') }])
new_event.remove('@timestamp')
event.append(new_event)
"
}
grok {
match => {
"request" => '"%{WORD:verb} %{URIPATHPARAM:urlpathparam}?(?: HTTP/%{NUMBER:httpversion})"'
}
patterns_dir => ["/home/data/logstash/patterns/"]
#patterns_dir => ["/usr/local/logstash/vendor/bundle/jruby/2.3.0/gems/logstash-patterns-core-4.1.2/patterns/"]
remove_field => [ "errinfo","request" ]
}
}
}
output {
#elasticsearch { host => localhost }
stdout { codec => rubydebug }
if [type] =~ "nginx-error-log" {
#redis{
# data_type => "channel"
# key => "logstash-nginx-%{+yyyy.MM.dd}"
#}
elasticsearch {
hosts => [ "${ELASTIC_HOST:'http://127.0.0.1:9200'}"]
index => "logstash-nginx-error-log-%{+YYYY.MM.dd}"
document_type => "data"
user => "xxx"
password => "xxx"
}
}else if [type] =~ "nginx-access-log" {
elasticsearch {
hosts => [ "${ELASTIC_HOST:'http://127.0.0.1:9200'}"]
index => "logstash-nginx-access-log-%{+YYYY.MM.dd}"
document_type => "data"
user => "xxx"
password => "xxx"
}
}
}
可以命名为logstash.conf
6 . 如部署到服务器，可使用FTP,scp,rsync,ansible等等工具上传到服务器(可选)
7 . 运行logstash进行测试，测试前，因为我们的logstash文件有使用到环境变量ELASTIC_HOST，主机地址可以自己进行定义。
export ELASTIC_HOST=[某服务器地址]
logstash -f -t logstash.conf ##检查配置是否正确
logstash -f logstash.conf ## 运行logstash
8. 如果想以服务方式运行logstash
cd /usr/local/logstash/bin/
./system-install --help
Usage: system-install [OPTIONSFILE] [STARTUPTYPE] [VERSION]
NOTE: These arguments are ordered, and co-dependent
OPTIONSFILE: Full path to a startup.options file
OPTIONSFILE is required if STARTUPTYPE is specified, but otherwise looks first
in /usr/local/logstash/config/startup.options and then /etc/logstash/startup.options
Last match wins
STARTUPTYPE: e.g. sysv, upstart, systemd, etc.
OPTIONSFILE is required to specify a STARTUPTYPE.
VERSION: The specified version of STARTUPTYPE to use. The default is usually
preferred here, so it can safely be omitted.
Both OPTIONSFILE & STARTUPTYPE are required to specify a VERSION.
我使用的为CentOS7系统，使用Systemd。如果想要在Systemd中定义环境变量那么。
cd /etc/systemd/system/
vim logstash.service
### 定义变量的行
Environment="KEY=VALUE"
ExecStart=/usr/local/logstash/bin/logstash "--path.settings" "/usr/share/logstash/config" ###修改服务执行脚本
9 . 添加系统的Logstash用户
useradd -s /sbin/nologin -M logstash
chown -R logstash.logstash /usr/local/logstash ## 改变logstash的属主属组，否则服务启动会报错。
10. 启动logstash
systemctrl start logstash
journalctl -u logstash ## 查看logstash的日志
额外
想要监控logstash的情况的话
在logstash的配置文件中
cd /usr/local/logstash/config
xpack.monitoring.elasticsearch.url : "Elasticsearch服务器地址"
xpack.monitoring.elasticsearch.username: logstash_system
xpack.monitoring.elasticsearch.password: xxx
最后
Logstash的功能很强大，还有一些其余的方案可以尝试，可以配合ELK与Docker一起使用，达到更灵活的效果
