Hi Karthic,
Based on your description, it seems like the DNS records and firewall rules have been set up correctly, but you are still facing issues while connecting and validating the Azure Migrate appliance. Here are some steps that you can follow to troubleshoot the issue:
Verify that the Private Endpoint is properly configured for the Azure Migrate appliance. Ensure that the Private Endpoint is pointing to the correct IP address of the Azure Migrate appliance, and that the required network traffic is allowed through the firewall.
Check the logs on the Azure Migrate appliance to identify the exact error message. This may provide more information about the cause of the issue.
Ensure that the Azure Migrate appliance is configured with the correct Azure Vault credentials. If the credentials are incorrect, the Azure Migrate appliance may fail to connect to the Azure Vault.
Check if any security policies or configurations are blocking the connection from the Azure Migrate appliance. This may include Network Security Groups (NSGs) or other firewall rules.
If the issue persists, you can reach out to Microsoft support for further assistance. Provide them with the error message and any relevant logs to help diagnose the issue.
I hope this helps you to resolve your issue.