Getting subdomains to work

[maslaral]

I've set up my subdomains to try to do some React development. However, I'm having issues where the 3000.mydomain.com just redirects back to my editor (i.e. mydomain.com). I'm using Caddy and have the settings that are in the setup guide, and I've edited my code-server.service file with the --proxy-domain mydomain.com command set.

Any suggestions for getting this to work properly? I'm using Google domains and I've also got my subdomain set up there (see screenshot below).

[jsjoeio]

Hey @maslaral - have you looked read the docs related for Proxying a Create React App by chance?

[maslaral]

Yeah, I've read through that and was able to get it to work. But had issues with routing in React. I thought it was possible (and recommended) to use subdomains instead.

[code-asher]

Based on the screenshot it looks like it's redirecting 3000.domain.com to domain.com. I think what you want instead is one of these:

1. An A record pointing 3000.domain.com to your IP (the same thing you probably did for domain.com).
2. A CNAME pointing 3000.domain.com to domain.com so it resolves to the same IP.

[code-asher]

No problem! Yeah, you'll need a wildcard certificate or you'll need to set up separate certs for each subdomain.

[maslaral]

I'm guessing wildcard certificates are handled via Caddy (at least in my case). Is there an example caddyfile I can look over?

[code-asher]

I actually haven't set up wildcard certificates using Caddy yet since they don't support my registrar so currently I just brute force it like a madman:

domain.com {
  reverse_proxy localhost:8080
}
3000.domain.com {
  reverse_proxy localhost:8080
}
3001.domain.com {
  reverse_proxy localhost:8080
}

And so on for each sub-domain I want.

Wildcard certificates through Caddy (via Let's Encrypt) require a DNS challenge (https://caddyserver.com/docs/automatic-https#wildcard-certificates) and I don't think they have a provider for Google domains yet (https://github.com/caddy-dns).

[maslaral]

Hmm, I'm still having issues with accessing the subdomain. I'm getting an ERR_NAME_NOT_RESOLVED error, even though I've exactly matched your setup. I'm wondering if adding the --proxy-domain flag in the .service file is working correctly.

[code-asher]

I think that means the browser isn't able to resolve the name to an IP address. It could mean the changes to DNS haven't propagated to you yet or that something is misconfigured.

You might try dig or ping against the sub-domain and see if you get the right IP address.