The customer reported a change in behavior after upgrading to OpenShift 4.18 with the Azure File CSI driver. On OCP 4.17, the CSI driver only validated/updated the worker subnet where the nodes are deployed. Volumes were successfully created even when other subnets in the same VNET were delegated to other services (e.g., Oracle). 

On OCP 4.18, the CSI driver iterates over all subnets in the VNET during CreateVolume and attempts to enable Microsoft.Storage Service Endpoint on each of them. This results in failures on subnets delegated to other services, generating the error: "Service endpoint(s) (Microsoft.Storage) are not permitted in a subnet with the following delegation(s): (Oracle.Database/networkAttachments)."

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