Due to a change in storage account naming in 4.17 Azure File CSI driver now alphabetically matches storage account of image registry operator instead of the one created by installer. Matching foreign accounts is by itself a flaw but would not break the CSI storage. However, if the registry is configured as private the CSI driver can not handle this setting (with defaults) and will fail to mount volumes because it does not have worker subnet added to allowed networks for the storage account it tries to use (the one from registry operator).

We have a solution proposed already that would prevent our driver from matching foreign storage accounts and would also ensure we don't use any private settings with Azure File CSI Driver as it's untested. However our QE team does not have enough capacity to properly test the change in 4.17.0 but would be able to test this later so we can ship it in z-stream.

The proposal here is to document this as a known issue and suggest users don't enable private image registry when using Azure File CSI until we release the fix in z-stream.