Reverse proxy and Reverse DNS for YunoHost installation

[tituspijean]

Potentially useless guidance, click here.

@nqo

What you are trying to achieve
Use the Redirect app to direct Yunohost’s main reverse proxy to itself, based on @tituspijean’s tip.

The context
This is my attempt to resolve my last remaining Yunohost install error. After this is resolved, I hope I can install apps without reverse proxy errors and send and receive email ok.

Your solution of “direct[ing] Yunohost’s main reverse proxy to itself” does not make sense. (I did not suggest that by the way )
We are missing very important information here:

• What apps are you trying to make available in YunoHost ?
• Where are they installed ?

You forgot to mention what is your “last remaining YunoHost installation error”.

@nqo

Redirect destination path: http://127.0.0.1

I see you keep redirecting back to localhost / 127.0.0.1. That might answer my second question and explain why you want to “direct YunoHost’s main reverse proxy to itself”. However if you only put http://127.0.0.1 you will ask the webserver to only serve whatever page is served at that specific page (spoiler: not much).

If your apps include their own webserver, or if they are containerized, usually they are accessible with an internal port, for example 8888. In that case, your destination path should be http://127.0.0.1:8888 (with or without a trailing slash, I cannot remember). private_proxy or public_proxy choice depends on whether or not you want visitors to log in as YunoHost users first.

@nqo

However, when I run Diagnostics, the error about reverse proxy remains unchanged throughout these experiments. Each time I get:

Reverse DNS is not configured for IPv6 […]

Have you mixed up or misread “reverse proxy” with “reverse DNS”? These are totally completely different things.

• Reverse Proxy makes your webserver fetch and re-serve webpages from another webserver, either local (apps providing their own webserver on a specific port, for example), or external (another server is on a network accessible by your Internet-facing server, and you want it to serve as conduit for it).

• Reverse DNS is literally a reversed DNS record. DNS records are held by the domain registrars and basically say “This domain points to that IP address”. Reverse DNS are held by the Internet Service Provider that manages the IP address, and basically say “This IP address is used by that domain”.

As stated in your screenshot, this is mostly important for emails, as a safety layer to mitigate impersonation of servers. A nefarious person might try to send emails that appear to be coming from domain X, with their server on IP address B. But if domain X DNS record points to address A, and the Reverse DNS for address A points to domain X, we can infer something is not right.

@nqo

‘Call your ISP and ask them to set up reverse proxy’ is not an instruction that is available equally to all. I cannot call them, or receive calls from them.

(from the other thread). Reverse proxy is not your solution here. Read your Diagnosis report again, and follow its suggestion. There should be a setting in your router or in your ISP management account to set the Reverse DNS. I understand calling them is not an option here, but they should have a proper documentation on Reverse DNS. If not, I am sure they have a support email address or a chat support?