I run Traefik on my unraid server as a docker container and wish to be able to have local and VPN access but no web access. I made an A record on CloudFlare pointing to the internal IP of Traefik and local access works fine. However the IP address changes when I turn on tailscale VPN, is it possible to have two A records pointing the same domain to both the internal IP of Traefik and the tailscale IP? I tried this and it didn't seem to work
In general you can have multiple IPs for a domain on DNS. When a browser/client does a lookup, the DNS server will return all IPs, then the browser/client will pick a random one.
If you only need a different IP inside your VPN, you need to check how to configure DNS inside the VPN, that can override the external setting.