Please explain this 502 Bad Gateway error

[Igor Sysoev]

On Thu, Dec 27, 2007 at 10:36:00PM +0530, just starting wrote:

> hi,
> 
> First of all my sincere thanks.
> 
> Error Log Entry : [2007/12/27 10:44:07 [error] 2625#0: *7 connect()
> failed (111: Connection refused) while connecting to upstream, client:
> 192.168.0.234, server: localhost, request:
> "GET /KdocProj/dboard.html?_dc=1198726407859 HTTP/1.0", upstream: "
> http://192.168.0.241:8080/KdocProj/dboard.html?_dc=1198726407859", host: "
> 192.168.0.241:8000"]
> 
> Let me explain a few things.
> 
> The machine where I am testing the hosting is 192.168.0.241.
> nginx is hosted on port 8000 and jetty on 8080 on the same machine mentioned
> above.
> 
> There is a statement in the error log like : "while connecting to upstream,
> client: 192.168.0.234,", please note that 192.168.0.234 is the local proxy
> server for internet access. So, what i think happening here is that nginx is
> trying to access the local jetty server via proxy.

The "client: 192.168.0.234" means that someone on 192.168.0.234 has connected
to nginx and request. nginx proxies the request to 192.168.0.241:8080.

Probably you should set "proxy_pass  http://127.0.0.1:8080" instead
of 192.168.0.241:8080.

> For Igor:
> >>>>The "Connection refused" usually means that backend does not listen
> on 192.168.0.241:8080 or its listen queue is full: it can not handle all
> requests.
> 
> I am the only one testing this implementation. So, I dont think the listen
> queue is full and also I made sure that jetty is listening on port 8080.

Then it's prbably firewall.


-- 
Igor Sysoev
http://sysoev.ru/en/