On Web platform, RoomKit large class, how to handle the issue where students cannot see the teacher's video when joining?

This problem may be caused by the CDN used by RoomKit not being configured with CNAME or HTTPS certificate. The troubleshooting method is as follows:

1. When encountering the problem, you can first open the browser console (taking Chrome browser as an example: press "F12" on the keyboard or right-click the mouse, select "Inspect" in the menu popup) > select "console" to check if there are any errors.
2. If the console shows an error "net::ERR_NAME_NOT_RESOLVED", please refer to Configure Domain CNAME to check if the domain CNAME is configured.
3. If the console shows an error "net::ERR_CERT_COMMON_NAME_INVALID", please contact ZEGOCLOUD Technical Support to confirm whether the CDN address has HTTPS certificate configured. If not, you need to purchase or download a free certificate (Nginx version) from the domain provider (Alibaba Cloud/Tencent Cloud, etc.), and send the certificate to technical support for certificate configuration.