Hello rongda lin ,
Thank you for reaching out on the Microsoft Q&A.
If you're being forced to enable DDoS protection for a Basic SKU public IP, it might be due to subscription or VNet-level settings rather than an Azure requirement.
- Basic SKU public IPs are not eligible for DDoS IP Protection (Docs)
- Azure provides default DDoS protection at no extra cost (Docs)
- Check if a DDoS Protection Plan is enabled at the subscription or VNet level
If the issue persists, try creating the IP via Azure CLI or PowerShell instead of the portal or contact Azure Support.
I hope this helps! If you have any further questions, feel free to ask.
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