Storage options on Google Cloud Platform

Read write once (RWO) block disk storage

OpenShift 4 brings along a storage provisioner which taps into the disk storage offering of the Google Compute Engine. The following storage classes are provided:

standard

Zonal standard persistent disks—Efficient and reliable block storage

regional

Regional standard persistent disks—Efficient and reliable block storage with synchronous replication across two zones in a region

ssd

Zonal SSD persistent disks—Fast and reliable block storage

regional-ssd

Regional SSD persistent disks—Fast and reliable block storage with synchronous replication across two zones in a region

Check Google Compute Engine Storage Options for the details on that storage.

Check Google Compute Engine Disk Pricing for the pricing of the storage options.

Standard class

If a PersistentVolumeClaim doesn’t request for a StorageClass explicitly, the StorageClass standard will be used to provision the PersistentVolume.

Minimum capacity per disk

The Google documentation of Storage options, mentions a minimum capacity per disk. This isn’t enforced but it directly has impact on the performace of that disk.

Read write many (RWX) file storage

Use of Cloud Storage is preferred. It’s the more reliable and cost effective solution.
The following is only available on request.

Filestore is the Google Cloud service for a file storage. Files stored in Filestore can be read and written from several sources at the same time.

Filestore can by used by OpenShift in two ways: a single instance which is shared across all PersistentVolumes of a StorageClass or an instance for each PersistentVolume.

Shared Instance

A single Filestore instance will be created. Since Filestore makes files accessible by NFSv3, the NFS Client Provisioner can then be leveraged. The provisioner will create a subdirectory for each PersistentVolume.

Dedicated Instance

The GCP Filestore CSI Driver allows to have a Filestore instance provisioned for each requested PersistentVolume.

Check the Cloud Filestore Pricing for the attached price tag.

The minimal size of a Filestore instance is 1TB for HDD and 2.5TB for SSD.