On Mon, Feb 01, 2021 at 03:11:57AM -0500, petrg wrote: Hi there,
> If I call the webpage from a connected PC (PC-browser) everything is working > fine. > But now I’d like to run a reverse-proxy (PC-proxy) in between. > So the PC-browser does not see the PC-device anymore. > This structure of a reverse proxy looks very basic for me. But I don’t get > it run. > > My configuration: > > PC-device > /path/index.html > <img src="/images/logo.jpg" …> > > nginx.conf > location /images/ > absolute_image_path > > PC-proxy > nginx.conf > location /device/ > proxy_pass 192.168.5.1/path > index.html > > PC-browser > url: 192.168.1.1/device/index.html > > => index.html will be loaded correctly from PC-device, because of the > proxy-pass configuration > => but the Logo-image, that will be loaded by the index.html, will not be > found. > So, how does a reverse-proxy load data for a webpage ? There is no magic; it does what you configure it to do. The browser makes a request to nginx; nginx handles that according to its config. Every request is independent. > How should nginx(PC-proxy) know, where to find the image-file > /images/logo.jpg that is asked for by the webpage ? You need to configure your nginx to do what you want it to do. PC-proxy needs to know what request to make to PC-Device, when PC-Browser asks PC-Proxy for /images/logo.jpg. If you look at the PC-Proxy nginx logs, they should show what that nginx saw, and what it did. > Or is it necessary that all data of the webpage has to be relative to the > starting point “192.168.1.1/device/index.html” ? > I am not sure if my misunderstanding is related to the webpage structure or > to the reverse-proxy function. Possibly both? I will try to explain. Your actual html page is on PC-device, in the file /something/path/index.html. It can include any or all of: <img src="one.jpg"> <img src="/path/two.jpg"> <img src="http://PC-device/path/three.jpg";> <img src="http://192.168.5.1/path/four.jpg";> to refer to things in the same directory, or <img src="/otherpath/five.jpg"> to refer to a thing in another directory. When the browser talks to PC-Device directly and asks for http://PC-device/path/index.html, it gets back the content, and then it tries to make five new requests, for http://PC-device/path/one.jpg, http://PC-device/path/two.jpg, http://PC-device/path/three.jpg, http://192.168.5.1/path/four.jpg, and http://PC-device/otherpath/five.jpg. All will probably work. When the browser talks to PC-proxy and asks for http://192.168.1.1/device/index.html it gets the same html back, and it makes five new requests for http://192.168.1.1/device/one.jpg, http://192.168.1.1/path/two.jpg, http://PC-device/path/three.jpg, http://192.168.5.1/path/four.jpg, and http://192.168.1.1/otherpath/five.jpg. The first will work because of your nginx config; the second and fifth will not work because you have not configured your nginx to make it work; and the other two will (probably) not go to nginx on PC-proxy, so no config there can help you. In your case, you are doing something like "five.jpg". So: you must either change the PC-device layout and html so that everything is below /somewhere/path *and* all links are relative (i.e. do not start with http: or with /); or change your nginx config so that you also have something like location /otherpath/ { proxy_pass http://PC-Device/images/; } location /path/ { proxy_pass http://PC-Device/path/; } (Although that second one would usually be written location /path/ { proxy_pass http://PC-Device; } -- see the docs for proxy_pass at http://nginx.org/r/proxy_path for details.) And you will also need to change the PC-device html so that all links are at least site-relative (i.e. do not start "http:"); or if the links do use "http:", they use the name that the world should see (something that resolves to PC-Proxy, not something that resolves to PC-Device). In general: * you reverse-proxy to something that you control * the thing you are reverse-proxying, needs not to fight being reverse-proxied * it is often simplest if you reverse-proxy a thing at the same point in the url-hierarchy that it thinks it is installed at. That is: if your content is all below http://PC-Device/path/, it is probably simplest to reverse-proxy that at http://PC-Proxy/path/. It is not compulsory; but it would have made "two.jpg" Just Work in the example above. Good luck with it, f -- Francis Daly fran...@daoine.org _______________________________________________ nginx mailing list nginx@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx
![http://PC-device/path/three.jpg"](http://PC-device/path/three.jpg"){kind=link}
![http://192.168.5.1/path/four.jpg"](http://192.168.5.1/path/four.jpg"){kind=link}
