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I understand you are facing an issue while connecting to a server located in China via Azure VPN. The error message indicates that the connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. You can try following the steps below and see if that helps in resolving the issue.
- Reset VPN Gateway: As the VPN was working initially, resetting an Azure VPN gateway or gateway connection is helpful if you lose cross-premises VPN connectivity on the VPN tunnels. You can follow the documentation here for implementation.
- If above does not help, you can enable Azure VPN Diagnostic Logs to help pinpoint the exact issue. You can take a look at P2SDiagnosticLog which can help you determine the cause of the issue.
- Additionally, you can also set-up a packet capture for you VPN Gateway to help pinpointing the exact issue.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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