If after you begin using Alibaba Cloud CDN, your users reported slow website access, errors, or files update failures, etc.
You could ask your users to access User Diagnostic Tools, and send you a snapshot for you to check if ldns and local IP address are normal.
Add your origin site and CDN domain name to your local hosts file. Example: edit
c:\Windows\System32\drivers\etc\hosts with IP first and domain name next (as in the following figure), then you can use the CDN domain name to visit your origin site directly rather than by using Aliaba Cloud CDN. If you still cannot visit your server origin site, it indicates that exception exists in you server origin site
Ping the domain name in the command prompt, which can be performed by you or the user. If the IP of the CDN pass the ping test, it indicates the CDN node is normal.
If all the previous operations cannot help locate problems, you can submit a ticket, and we will help you to troubleshoot.