Following the merging of #14959 - Gitea is a lot more strict regarding the interpretation of `X-Real-IP` and `X-Forwarded-For` headers.
This PR updates the fail2ban documentation to include hints to set: `REVERSE_PROXY_TRUSTED_PROXIES` and `REVERSE_PROXY_LIMIT` appropriately.
See discussion in #16443
Co-authored-by: zeripath <art27@cantab.net>
```
proxy_set_header X-Real-IP $remote_addr;
```
+
+The security options in `app.ini` need to be adjusted to allow the interpretation of the headers
+as well as the list of IP addresses and networks that describe trusted proxy servers
+(See the [configuration cheat sheet](https://docs.gitea.io/en-us/config-cheat-sheet/#security-security) for more information).
+
+```
+REVERSE_PROXY_LIMIT = 1
+REVERSE_PROXY_TRUSTED_PROXIES = 127.0.0.1/8 ; 172.17.0.0/16 for the docker default network
+```