I may not have been clear, but I understand and fully support their right to charge for software and services. I just haven&#x27;t worked on any projects for which their prices fit in to the calculation.<p>As to documentation on nginx.org that doesn&#x27;t apply to the open source edition, see <a href="http:&#x2F;&#x2F;nginx.org&#x2F;en&#x2F;docs&#x2F;http&#x2F;ngx_http_upstream_module.html#sticky" rel="nofollow">http:&#x2F;&#x2F;nginx.org&#x2F;en&#x2F;docs&#x2F;http&#x2F;ngx_http_upstream_module.html#...</a> -- there are quite a few more, that&#x27;s just the last one I tried to use.