日志解析

1）基本配置

# cat /etc/nginx/nginx.conf -n
    40        access_log /var/log/nginx/access.log;
    41        error_log /var/log/nginx/error.log;
注意：
     nginx日志属性设置的完整格式是：
         属性名称 access_log
         存储位置 /var/log/nginx/access.log
      日志格式 位置为空表示使用默认的combined 日志格式。它是通过log_format设置的

2）默认日志格式

log_format combined '$remote_addr - $remote_user [$time_local] '
                    '"$request" $status $body_bytes_sent '
                    '"$http_referer" "$http_user_agent"';

案例

1）设置日志格式

# vim /etc/nginx/nginx.conf

# Logging Settings
##  设定日志格式的方法： log_format 格式名称 "日志表现样式"
   log_format proxy_format '$remote_addr - $remote_user [$time_local] '
                  '"$request" $status $body_bytes_sent "$http_referer"'
                  '"$http_user_agent" "$http_x_real_ip" "$http_x_forwarded_for"';

2）使用日志格式

access_log 日志路径 格式名称;

3）负载均衡配置文件

# vim /etc/nginx/conf.d/upstream.conf
upstream backends {
  server 172.16.179.131:10086;
}
server {
  listen 8080;
  server_name localhost;
  location / {
    proxy_pass http://backends;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  }
}

4）后端代理配置文件

# vim /etc/nginx/conf.d/backend.conf
server {
  listen 172.16.179.131:10086;
  location / {
    proxy_pass http://172.16.179.130:10087/;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  }
}

server {
  listen 172.16.179.131:10087;
  root /var/www/html/app1/;
  access_log /var/log/nginx/app1/access.log proxy_format;
  real_ip_header X-Forwarded-For;
  set_real_ip_from 172.16.0.0/16;
  real_ip_recursive on;

  location / {
    root /var/www/html/nihao/;
    try_files $uri $uri/ =404;
  }
}

5）准备后端服务文件

mkdir -p /var/www/html/app1/
echo '<h1>backend_app1</h1>' > /var/www/html/app1/index.html
mkdir /var/log/nginx/app1 -p

6）检查nginx配置后重载服务

/usr/sbin/nginx -t
systemctl reload nginx
netstat -tnulp | grep nginx

7）查看效果

在多台主机上执行如下命令
curl http://172.16.179.131

8）查看app1日志

172.16.179.1 - - [04/Jun/2019:20:24:32 +0800] "GET / HTTP/1.0" 304 0 "-""curl/7.47.0" "172.16.179.1" "172.16.179.1, 172.16.179.131"
172.16.179.130 - - [04/Jun/2019:20:26:13 +0800] "GET / HTTP/1.0" 200 23 "-""curl/7.47.0" "172.16.179.130" "172.16.179.130, 172.16.179.131"