I have implemented a cloudflared tunnel on an internal intranet network, and it works very well. I have set up three subdomains on the local internal network. For security reasons, I would like two of these subdomains to be accessible only on the local network. Is this possible? Specifically, I want users to access the subdomain mysubdomain.domain.com only from the internal 192.168.1.0/24 network and make it inaccessible from the internet.
Yes,it is possible. you can check here Private networks · Cloudflare Zero Trust docs where it explains that end users must connect their device to Cloudflare and enroll in your Zero Trust organization once that is done they are on the private local network which allows them to request your private subdomain (Private DNS · Cloudflare Zero Trust docs)