Unable to access EC2 instance service through domain name

It could be that the DNS servers in China are not resolving your domain name properly. You can try using a public DNS service like Google Public DNS (8.8.8.8 and 8.8.4.4) or Cloudflare DNS (1.1.1.1) to check if that resolves the issue.

The Great Firewall of China is known for blocking or limiting access to certain websites, services, and IP addresses. It's possible that your domain or IP address might be affected by these restrictions. In this case, using a VPN or proxy is often the only way to bypass these restrictions.

To diagnose the issue, try the following steps:

• Check if your domain is resolving correctly using tools like nslookup, dig, or an online DNS checker.
• Verify that your EC2 instance's security group and network ACLs are configured to allow incoming traffic on the required ports (e.g., 80 for HTTP, 443 for HTTPS).
• Test access to your domain from multiple locations and networks within China to rule out any localized issues.