With the recent release of Red Hat OpenShift Container Platform 3.9, you will now have the convenience of deploying Container-Native Storage (CNS) 3.9 built on Red Hat Gluster Storage as part of the normal OpenShift deployment process in a single step. At the same time, major improvements in ease of operation have been introduced to give you the ability to monitor provisioned storage consumption, expand persistent volume (PV) capacity without downtime, and use a more intuitive naming convention for persistent volume names.

For easy evaluation of these features, an OpenShift Container Platform (OCP) evaluation subscription now includes access to CNS evaluation binaries and subscriptions.

New features in Container-Native Storage 3.9

Addition of volume metrics—Volume consumption metrics data (e.g., volume capacity, available space, number of inodes in use, number of inodes free) for CNS is now available. These volume metrics can be viewed using Prometheus. This enables you to monitor storage capacity and consumption trends and take timely actions to ensure applications do not get impacted.

Online expansion of provisioned storage—You can now expand the CNS-backed persistent volumes (PVs) within OpenShift by editing the corresponding claim (oc edit pvc <claim_name>) with new desired capacity (‘spec→ requests → storage: new value’).  This opt-in feature is enabled by configuring the StorageClass for CNS with the parameter allowVolumeExpansion set to “true,” enabling the feature gate `ExpandPersistentVolumes` and including a new admission controller called `PersistentVolumeClaimResize.` You can now dynamically resize storage volumes attached to containerized applications without needing to first detach and then attach a storage volume with increased capacity, which enhances application availability and uptime.

Custom volume naming—Before this release, the names of the dynamically provisioned GlusterFS volumes were auto-generated with unique id number (vol_<UUID>). This release allows you to add a custom volume name prefix, again by parameterizing the StorageClass (`volumenameprefix: myPrefix`), for easier identification of volumes in the GlusterFS backend. The new GlusterFS volumes backing the CNS PVs will be created with the volume name prefix, project name/namespace, claim name and UUID (<myPrefix>_<namespace>_<claimname>_UUID), making it easier for you to automate day-2 admin tasks like backup and recovery, policy application based on pre-ordained volume nomenclature, and other day-2 housekeeping tasks.

You can read more about the new features at the Red Hat Blog.

By  Annette Clewett, Humble Chirammal, Daniel Messer, and Sudhir Prasad, originally published by Red Hat