When I reverse proxy to a public echo service, I can make this work using
the server name directly, but I get an HTTP 403 if I use an upstream server
block pointing to the same domain.
Simple Scenario:
```
location / {
proxy_pass http://rve.org.uk/utils/echo-nocache.cgi/freg/;
}
```
Upstream scen
When I reverse proxy to a public echo service, I can make this work using
the server name directly, but I get an HTTP 403 if I use an upstream server
block pointing to the same domain.
Simple Scenario:
```
location / {
proxy_pass http://rve.org.uk/utils/echo-nocache.cgi/freg/;
}
```
Upstream scen
