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Hands-on Lab·Kubernetes and Cloud Native Associate

PVC Expansion and Volume Snapshots

Patch a PVC from 64Mi to 128Mi and it reports 128Mi requested against 64Mi actual, with FileSystemResizePending. The volume grew; the filesystem has not. Recreate the Pod and both agree - and the other StorageClass on this cluster cannot do it at all.

Storage Guide 23 of 46 Intermediate

Written against the versions above. Behaviour depends on the CSI driver. The two-phase resize and the conditions below are part of the Kubernetes contract; whether an online resize needs a remount is up to the driver.

Two StorageClasses are installed: one CSI-backed, one not. The difference in what they can do is the subject.
Server NameIP AddressOSRolesCPURAMHDD
CKA1001192.168.0.175Ubuntu 26.04 LTSControl Plane Node2 Core4 GB50 GB
CKA1001-NODE02192.168.0.177Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB

Before you start

  1. Two classes, two capability sets

  2. Claim it, mount it, write to it

  3. Patch it larger, and read the disagreement

  4. Recreate the Pod and they agree

  5. Snapshot it

  6. The other class cannot

Official sources