Hi @minsun kim ,
Thanks for posting this question in Q&A forum.
You can run a tcpping command from the command prompt of your PC and check the connectivity.
ping the ip address : tcpping 0.0.0.0:443
Ping the hostname: tcpping appname.azurewebsites.net:443
You can get the inbound public ip address of the app service from the Networking tab in the app service portal
Hope this helps! Feel free to reach out to me if you have any questions or concerns.
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