What and when subdomains are needed?

I’ve installed jitsi-meet package on a fresh Debian GNU/Linux 10, intended to be only dedicated to Jitsi Meet (open for the moment).
This is an LXC container in a desktop computer, both with their own IP address.
Only by reverse-proxying* https website from another container (with Apache) to my jitsi container (no port forwarding), this already allows to connect Meet website and place chat sessions between users.

I’ve read that for some setups an “auth” subdomain is needed. I don’t know if it is for my scenario or not (users can already set a password for their meeting), and I don’t know if some other subdomains are needed for webRTC meeting service.

(*) mymeets.example.net with Apache’s ProxyPass to target container.
+Q: Do I need some special configuration when doing HTTPS reverse proxy? (I’ve own x509 certificates already working; not this matter).

I mean, if my jitsi meeting portal is mymeets.example.net , when do I need to assign also subdomains.mymeets.example.net such as auth.mymeets.example.net ?
Never? Sometimes? More than “auth”?

Thank you

Read the secure documentation, all those subdomains are just prosody virtual hosts and are internal for the system, no dns or certificate or anything is needed for those.