I have a few selfhosted services, but I’m slowly adding more. Currently, they’re all in subdomains like linkding.sekoia.example etc. However, that adds DNS records to fetch and means more setup. Is there some reason I shouldn’t put all my services under a single subdomain with paths (using a reverse proxy), like selfhosted.sekoia.example/linkding?
Generally a hostname based reverse proxy routes requests based on the host header, which some tools let you set. For example, curl:
curl -H 'Host: my.local.service.com' http://192.168.1.100here 192.168.1.100 is the LAN IP address of your reverse proxy and my.local.service.com is the service behind the proxy you are trying to reach. This can be helpful for tracking down network routing problems.
If TLS (https) is in the mix and you care about it being fully secure even locally it can get a little tricky depending on whether the route is pass through (application handles certs) or terminate and reencrypt (reverse proxy handles certs). Most commonly you’ll run into problems with the client not trusting the server because the “hostname” (the LAN IP address when accessing directly) doesn’t match what the certificate says (the DNS name). Lots of ways around that as well, for example adding the service’s LAN IP address to the cert’s subject alternate names (SAN) which feels wrong but it works.
Personally I just run a little DNS server so I can resolve the various services to their LAN IP addresses and TLS still works properly. You can use your /etc/hosts file for a quick and dirty “DNS server” for your dev machine.
TLS SNI will take care of that issue just fine, most reverse proxies will just handle it for you especially if you use certbot i.e. usually letsencrypt