proxy pass keepalive without upstream module

Hi
I read here that keepalives to backend can be enabled with the upstream
module
(http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive)
But can they be used without defining an upstream block? Just a simple
proxy_pass as the backend is a variable in my case: 'proxy_pass $proxy_to;'

Many thanks

_______________________________________________
nginx mailing list
nginx@nginx.org
http://mailman.nginx.org/mailman/listinfo/nginx