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Hands-on Lab·Certified Kubernetes Administrator

Expanding a PersistentVolumeClaim

Growing a volume under a running Pod. This reads the two size fields that matter, acts on the condition the cluster raises, and shows what a class that cannot expand does instead.

Storage Guide 69 of 103 Intermediate

Written against the versions above. Driver behaviour varies: some finish a filesystem resize online. This one asks for a Pod restart, which is the case worth planning for.

Four nodes with the CSI hostpath driver installed, providing an expandable class next to a local-path one that is not.
Server NameIP AddressOSRolesCPURAMHDD
CKA1001192.168.0.175Ubuntu 26.04 LTSControl Plane Node2 Core4 GB50 GB
CKA1001-NODE01192.168.0.176Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE02192.168.0.177Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE03192.168.0.178Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB

Before you start

  1. A claim, bound and in use

  2. Can this class even grow

  3. Ask for more, and read the two numbers

  4. Restart the Pod, which is what the condition asked for

  5. The claim that cannot grow at all

Official sources

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