Nginx double requests for my upstreams?

[funkdoobiest]

Hello,

Maxim Dounin Wrote:
-------------------------------------------------------
> Hello!
> 
> On Sun, Jun 07, 2009 at 03:35:41PM -0400,
> funkdoobiest wrote:
> 
> > Hi Maxim,
> > 
> > Maxim Dounin Wrote:
> >
> --------------------------------------------------
> -----
> > > Hello!
> > > 
> > > On Fri, Jun 05, 2009 at 07:59:13AM -0400,
> > > funkdoobiest wrote:
> > > 
> > > > Hi,
> > > > 
> > > > I have a strange behavior for my site load
> > > balanced with nginx.
> > > > I have 1 Loadbalancer with nginx and 3
> servers
> > > with apache.
> > > > 
> > > > sometimes a request  is doubled and send to
> 2 of
> > > my apache webservers.
> > > > this is a big problem for me, because this
> is
> > > sometimes a requests that is doing a
> payement.
> > > > I checked this behavior with doing a log of
> all
> > > my payment transactions and there a some
> > > transactions
> > > > for the same person double at the same
> second!
> > > (the user can't do this at the website,
> because I
> > > send the form which is doing the request with
> JS
> > > and ask the User if he really wants to pay and
> so
> > > on)
> > > 
> > >
> http://wiki.nginx.org/NginxHttpProxyModule#proxy_n
> 
> > > ext_upstream
> > > 
> > > Maxim Dounin
> > 
> > Thank you for your help. I set
> proxy_next_upstream to off, but there are still
> double requests :-(
> 
> It doesn't looks like nginx problem.  Try checking
> logs (frontend 
> and backend ones) - probably your javascript code
> just does 
> something wrong.
> 
> Maxim Dounin

I checked it about 100 times. I checked the logs also. It's not my script.
The requests are at the same second. If i disable the loadbalancer (in this case nginx) double request are stopping.

Jan

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,2644,2706#msg-2706