Does it possible to submit duplicated request with the proxy_next_upstream on

Server NGINX
1

Hi all:
I am wondering if I set:
proxy_next_upstream error timeout;
Fox example , if the requested service is a counter , I issue the
request use the interface http://example.com/incr . The request is
failed on my first host A, then it is passed to the second host B , is
the counter likely be added twice ?

thanks .

2

Can any one help ?

2014/1/3 ȫ [email protected]

3

Unless the request is getting que’d while there is a short wait for host
A
to get online AND fail-over is also happening, its not likely to be
added
twice.

Posted at Nginx Forum:

4

renenglish Wrote:

Sorry I can’t get it .

If host A has added the counter and failed to response, the request
would be failed over to host B with successful response, so the
counter would be added twines. Wouldn’t it ?

Then a condition must occur where host A fails right after processing
the
request, they usually fail before accepting a request, it also depends
on
the timeout for a request. And it also depends what nginx considers a
fail,
nginx might not fail a host when it does not return from accepting a
request.

You will have to simulate this to find out the conditions for a fail.

Posted at Nginx Forum:

5

OK. Thank you very much . I will do an experiment to find out this

2014/1/16 itpp2012 [email protected]

6

Sorry I cant get it .

If host A has added the counter and failed to response, the request
would be failed over to host B with successful response, so the counter
would be added twines. Wouldnt it ?
2014114գ5:48itpp2012 [email protected] д