Re: client closed prematurely connection в режиме proxy

[Denis F. Latypoff]

27.04.2012, 17:46, "Sergey Kobzar" <sergey.kobzar at itcraft.org>:
> Nginx в режиме прокси (фронтэнд):
>
> user nginx nginx;
> worker_processes 24;
>
> error_log /var/log/nginx/error.log info;
>
> events {
>          worker_connections 1024;
>          use epoll;
> }
>
> http {
>          include /etc/nginx/mime.types;
>          default_type application/octet-stream;
>
>          log_format main
>                  '$remote_addr - $remote_user [$time_local] '
>                  '"$request" $status $bytes_sent '
>                  '"$http_referer" "$http_user_agent" '
>                  '"$gzip_ratio" '
>                  '$upstream_addr $upstream_status';
>
>          client_header_timeout 10m;
>          client_body_timeout 10m;
>          keepalive_timeout 75 20;
>          send_timeout 10m;
>          server_tokens off;
>          client_max_body_size 40m;
>
>          sendfile on;
>          tcp_nopush on;
>
>          proxy_buffer_size 128k;
>          proxy_buffers 8 64k;
>          proxy_connect_timeout 5;
>          proxy_intercept_errors on;
>
>          set_real_ip_from 127.0.0.1;
>          real_ip_header X-Real-IP;
>
>          upstream backend {
>                  server 10.17.92.2  max_fails=3 fail_timeout=300s;
>                  server 10.17.92.12 max_fails=3 fail_timeout=300s;
>                  server 127.0.0.1 backup;
>                  ip_hash;
>          }
>
>          upstream backend_static {
>                  server 10.17.92.2  max_fails=3 fail_timeout=300s;
>                  server 10.17.92.12 max_fails=3 fail_timeout=300s;
>                  server 127.0.0.1 backup;
>          }
>
>          server {
>                  listen 127.0.0.1;
>                  server_name localhost;
>
>                  access_log /var/log/nginx/localhost_access.log main;
>                  error_log /var/log/nginx/localhost_error.log info;
>
>                  location / {
>                          error_page 502 504 /errors/500.html;
>                          return 500;
>                  }
>
>                  location ^~ /errors/ {
>                          root /home/www/localhost/htdocs;
>                          expires max;
>                  }
>          }
>
>          server {
>                  listen 80 default;
>                  server_name localhost;
>
>                  access_log /var/log/nginx/default_access.log main;
>                  error_log /var/log/nginx/default_error.log info;
>
>                  location / {
>                          proxy_pass http://backend;
>
>                          proxy_set_header Host $host;
>                          proxy_set_header X-Real-IP $remote_addr;
>                          proxy_set_header X-Forwarded-For
> $proxy_add_x_forwarded_for;
>                  }
>
>                  error_page 500 502 504 /errors/500.html;
>
>                  location ^~ /errors/ {
>                          root /home/www/localhost/htdocs;
>                          expires max;
>                  }
>          }
>
> На фронтэнде:
> 66.249.73.15 - - [27/Apr/2012:11:23:22 +0100] "GET ... HTTP/1.1" 504
> 9700 "-" "Mozilla/5.0 (compatible; Googlebot/2.1;
> +http://www.google.com/bot.html)" "-" 10.17.92.12:80, 10.17.92.2:80 504, 504
> 66.249.73.209 - - [27/Apr/2012:11:23:23 +0100] "GET ... HTTP/1.1" 504
> 9700 "-" "Mozilla/5.0 (compatible; Googlebot/2.1;
> +http://www.google.com/bot.html)" "-" 10.17.92.12:80, 10.17.92.2:80 504, 504
> 66.249.73.15 - - [27/Apr/2012:11:23:23 +0100] "GET ... HTTP/1.1" 500
> 9676 "-" "SAMSUNG-SGH-E250/1.0 Profile/MIDP-2.0 Configuration/CLDC-1.1
> UP.Browser/6.2.3.3.c.1.101 (GUI) MMP/2.0 (compatible;
> Googlebot-Mobile/2.1; +http://www.google.com/bot.html)" "-" 127.0.0.1:80 500
>
> На бэкенде на тот же запрос:
> access log:
> 66.249.73.15 - - [27/Apr/2012:11:23:22 +0100] "GET ... HTTP/1.0" 499 0
> "-" "Mozilla/5.0 (compatible; Googlebot/2.1;
> +http://www.google.com/bot.html)" "-"
>
> error_log:
> 2012/04/27 11:23:22 [info] 9804#0: *206566 client closed prematurely
> connection, so upstream connection is closed too while sending request
> to upstream, client: 66.249.73.15, server: localhost, request: "GET ...
> HTTP/1.0", upstream: "fastcgi://127.0.0.1:9001", host: "www.test.com"
>
> Т.е. общая картина:
>
> 1. Клиент закрыл соединение - на бэкенде получили 499
> 2. Вернули фронтенду 504
> 3. 3 подобные ситуации и бэкэнд выкидываем из пула
>
> Как-то это неправильно IMO. Т.е. несколько клиентов закрывших соединение
> могут завалить всю систему. Уменьшать max_fails=3 fail_timeout=300s не
> хочу, т.к если один из бэкжндов действительно в дауне, начинаются проблемы.
>
> Как правильно решить подобную ситуацию?
>

http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_ignore_client_abort

> Спасибо.
>

-- 
br, Denis F. Latypoff.