How to create custom error 502 nginx in core of nginx (not using redirect to error page)?

Question

Sometimes I get an issue with error 502 when httpd service is down. But only in 1 minute the website come back.

I need to custom the 502 message to ask user to wait for 1 minute then refresh page, or embed JavaScript or meta refresh tag to auto refresh page after 1 minute. Page's URL must be the same to make refresh effect

Notice that I know about custom error page redirect eg location = /502.html, but that type of custom error page will redirect user to other page, if they will refresh page they will got error page again.

Any idea will be very helpful.

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EDIT UPDATE for more detail 10/06/2012.

My nginx config:

user  nobody; # no need for more workers in the proxy mode worker_processes  24; error_log  /var/log/nginx/error.log crit; #worker_rlimit_nofile 20480; events {  worker_connections 109024; # increase for busier servers  use epoll; # you should use epoll here for Linux kernels 2.6.x }  http {  server_name_in_redirect off;  server_names_hash_max_size 2048;  server_names_hash_bucket_size 256;  include    mime.types;  default_type  application/octet-stream;  server_tokens off;  sendfile on;  tcp_nopush on;  tcp_nodelay on;  keepalive_timeout  20;   ignore_invalid_headers on;  client_header_timeout  50m;  client_body_timeout 50m;  send_timeout     20m;  reset_timedout_connection on;  connection_pool_size  2048;  client_header_buffer_size 256k;  large_client_header_buffers 4 256k;  client_max_body_size 20M;   client_body_buffer_size 300k;  request_pool_size  32k;  output_buffers  14 32k;  postpone_output  1460;  proxy_temp_path  /tmp/nginx_proxy/;  proxy_cache_path /dev/shm/nginx levels=1:2 keys_zone=wwwcache:45m inactive=5m max_size=1000m;  client_body_in_file_only off;  access_log off;  open_log_file_cache off;  #log_format bytes_log "$msec $bytes_sent .";  include "/etc/nginx/vhosts/*"; } 

and vhost config:

server {  #         error_log /var/log/nginx/vhost-error_log warn;           listen 123.30.137.66:80;           server_name xaluan.net mtvvui.com www.daiduong.com.au www.xaluan.net xaluan.com www.xaluan.com www.daiduongrestaurant.net veryzoo.com www.mtvvui.com www.xaluan.org www.veryzoo.com daiduongrestaurant.net xaluan.org daiduong.com.au; #          access_log /usr/local/apache/domlogs/xaluan.net combined;           root /home/xaluano/public_html;           location / {       if ($http_cache_control ~ "max-age=0") {                 set $bypass 1;           }        location  ~.*\.(3gp|gif|jpg|jpeg|png|ico|wmv|avi|asf|asx|mpg|mpeg|mp4|pls|mp3|mid|wav|swf|flv|htm|txt|js|css|exe|zip|tar|rar|gz|tgz|bz2|uha|7z|doc|docx|xls|xlsx|pdf|iso)$  {       #root /home/xaluano/public_html;       #proxy_cache wwwcache;       #proxy_cache_valid  200 15m;       #proxy_cache_bypass $bypass;           expires 1d;           #try_files $uri @backend;       proxy_pass http://123.30.137.66:8081;           }           error_page 405 = @backend;           add_header X-Cache "HIT from Backend";       #proxy_set_header Server "Caching-Proxy";           #add_header X-Cache-Vinahost "HIT from Backend";       proxy_pass http://123.30.137.66:8081;           include proxy.inc;            }             location @backend {           internal;           proxy_pass http://123.30.137.66:8081;           include proxy.inc;           }           location ~ .*\.(php|jsp|cgi|pl|py)?$ {           #proxy_cache wwwcache;       #proxy_cache_valid  200 15m;        proxy_pass http://123.30.137.66:8081;           include proxy.inc;           }           location ~ /\.ht {           deny all;           }       } 

== the case test..

If Apache httpd service stops: #service httpd stop

Then open in browser this link: http://www.xaluan.com/modules.php?name=News&file=article&sid=123456 You will see the 502 error with the same URL on browser address.

== Custom error page I need the config which will help when Apache fail, will show the custom message telling user to wait for 1 minute for service back, then refresh current page with same URL (refresh I can do easy by JavaScript), Nginx does not change URL so JavaScript can work out.

Answer 1

I found an answer that works for me. In the vhost config file, I put right at the end of the server block, before closing brace:

 error_page 502 /502.html;  location = /502.html {        root  /home/xaluano/public_html;    } 

Of course I also need to create a file 502.html at my domain root, with the meta-tag refresh, and java-script auto refresh.

The content of html page is:

<head> <meta http-equiv="refresh" content="40" />  </head> <body> <script language="JavaScript" type="text/javascript"> /*<![CDATA[*/ var TimerVal = 40; var TimerSPan = document.getElementById("CDTimer"); function CountDown(){    setTimeout( "CountDown()", 1000 );    TimerSPan.innerHTML=TimerVal;    TimerVal=TimerVal-1;    if (TimerVal<0) { TimerVal=0;    location.reload(true);  //   window.location.href = "http://www.xaluan.com";    } //improvement by vivalibre, tq  } CountDown(); /*]]>*/ </script>  </body> 

Answer 2

http://nginx.org/r/error_page

Note that error_page 502 /502.html; performs internal redirect. It does not change the URL in browser address bar.