http://www.lc365.net/blog/b/23997/
499 is a nginx custom state code, which has an explanation of this status code in the Src/http/ngx_http_special_response.c file.
494: The request head is too big
495:HTTPS Certificate Error
496:https No certificate
497:http to HTTPS
498: Cancel
499: The client closes the link (server-side processing time is too long, the client "impatient", disconnected the link. )
Common cases where the 499 error occurred:
1, it is true that the client shut down the connection, or the connection timeout, no matter how many times you set the timeout is not the original PHP process is not enough (the default test environment to open 5 sub processes)
Solution: Improve the number of PHP processes, problem solving.
2, Nginx to a never open back-end, client request timeout, active disconnect, log status record is 499, the number of bytes sent is 0.
FIX: Replace the back end that can be opened
3, open Nginx Access.log found in the last commit is the HTTP1.1499 0-such errors, but the use of Port +ip direct access to the backend server does not exist, later test Nginx found that if two submitted post too fast will appear 499 , it appears that Nginx is considered an unsafe connection and actively rejects the client's connection.
Proxy_ignore_client_abort on;
Don ' t know if this is safe.
That is, to configure the parameter proxy_ignore_client_abort on, which means that the proxy server does not primarily actively shut down client connections. With this configuration restart Nginx, the problem is solved. It's just a little bit less secure, but it's much better than always appearing to be unable to find a server.