FunctionVpcConfig

The VPC security groups and subnets that are attached to a Lambda function. When you connect a function to a VPC, Lambda creates an elastic network interface for each combination of security group and subnet in the function's VPC configuration. The function can only access resources and the internet through that VPC. For more information, see VPC Settings. When you delete a function, CFN monitors the state of its network interfaces and waits for Lambda to delete them before proceeding. If the VPC is defined in the same stack, the network interfaces need to be deleted by Lambda before CFN can delete the VPC's resources. To monitor network interfaces, CFN needs the `ec2:DescribeNetworkInterfaces` permission. It obtains this from the user or role that modifies the stack. If you don't provide this permission, CFN does not wait for network interfaces to be deleted.