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To secure the public IP for the frontend of Azure Application Gateway for Containers, it is recommended to use Azure Application Gateway with Web Application Firewall (WAF) or you can use Azure firewall which can protect all traffic from l3 to l7
For more information, you can refer to the following Azure documentation:
- Best practices and considerations for Azure Container Instances
- Protect Azure Container Apps with Web Application Firewall on Application Gateway
- Use Azure Firewall to protect Azure Kubernetes Service (AKS) clusters
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Thanks
Deepanshu