> Ok. So the upstream block has to be in the nginx.conf. I thought I
> could
> this one export to a separate file, too.

yes, you can (include your upstream-config and any other part).
you just need to place it into the right context, e.g. inside
a http { ... } - block and not inside a server { ... } - block

http://wiki.nginx.org/HttpUpstreamModule#upstream

>
> I was wondering why I still got the error message after I deleted the
> upstream block in nginx.conf and had it only in my included file. So
> the
> upstream configuration must be in nginx.conf?

every upstream-config for each of your server-parts gets a **unique** name,

what does $ grep -Rn "loadbalancer" /etc/nginx/*
gives you back? might be just a typo.


>