Feature Overview (aka. Goal Summary)

We GAed filestore CSI in 4.14 however we are missing test and documentation for how to use it in a shared VPC environment. 

Shared VPC simplifies network management, allows consistent network policies, and provides a centralized view of network resources. It's important that the CSI drivers we ship support the OCP deployment models.

https://docs.openshift.com/container-platform/4.14/installing/installing_gcp/installing-gcp-user-infra-vpc.html#installing-gcp-user-infra-vpc

Goals (aka. expected user outcomes)

Document how to use filestore CSI in a shared VPC environment

Requirements (aka. Acceptance Criteria):

The CSI driver should pass the usual tests when OCP is deployed with a shared VPC.

Use Cases (Optional):

As an admin I want my user to consume FileStore CSI when OCP is deployed on GPC with shared VPC.

Questions to Answer (Optional):

Does the driver support it already? Is it a testonly feature?

The upstream driver doc mentions that shared VPC is supported with SC parameters

https://github.com/kubernetes-sigs/gcp-filestore-csi-driver/blob/master/README.md#supported-createvolume-parameters

Currently, admins need to create a SC manually so there should not be any operator work needed.

Out of Scope

This feature is limited to the shared VPC use case

Background

Shared VPC is gaining traction specially for large customers as is facilitate management for multi projects.

Customer Considerations

Provide any additional customer-specific considerations that must be made when designing and delivering the Feature. Initial completion during Refinement status.

Documentation Considerations

Doc impact should be minimal: add a new Shared VPC sub section that show the SC parameters needed to configure the driver. 

Interoperability Considerations

It can benefit OSD as it now supports shared VPC