𝗟𝗲𝘁’𝘀 𝗧𝗮𝗹𝗸 𝗔𝗯𝗼𝘂𝘁 𝗣𝗩 𝗠𝗶𝗴𝗿𝗮𝘁𝗶𝗼𝗻!🚀

October 10, 2025

This content originally appeared on DEV Community and was authored by Anil Kumar

𝗛𝗲𝗹𝗹𝗼 𝗖𝗹𝗼𝘂𝗱𝗲𝗲𝘀 !

𝗟𝗲𝘁’𝘀 𝗧𝗮𝗹𝗸 𝗔𝗯𝗼𝘂𝘁 𝗣𝗩 𝗠𝗶𝗴𝗿𝗮𝘁𝗶𝗼𝗻!
𝐀𝐧𝐢𝐥: Hey Rakhul! Have you ever faced a challenge where you needed to upgrade storage, migrate to a different provider, or change storage classes?
𝐑𝐚𝐤𝐡𝐮𝐥: Yes, Anil! But honestly, I have no idea how to do it. Can you guide me?
𝐀𝐧𝐢𝐥: Of course! No worries, I’ll explain it in a simple way. Let’s dive in!

𝐖𝐡𝐲 𝐃𝐨 𝐖𝐞 𝐍𝐞𝐞𝐝 𝐭𝐨 𝐌𝐢𝐠𝐫𝐚𝐭𝐞 𝐃𝐚𝐭𝐚 𝐟𝐫𝐨𝐦 𝐎𝐧𝐞 𝐏𝐕 𝐭𝐨 𝐀𝐧𝐨𝐭𝐡𝐞𝐫?
Upgrading Storage Classes – Moving from an old, slower storage class (standard) to a new, faster one (ssd).
Switching Cloud Providers – Migrating from AWS EBS → Google Persistent Disk or any other provider.
Scaling Storage – If your PV is full and cannot be resized, you need a bigger PV.
Stateful Application Upgrades – Moving a MySQL database or other persistent apps to a new PV.
Backups & Disaster Recovery – Keeping data safe from accidental deletion, corruption, or failures.

𝐏𝐫𝐞-𝐑𝐞𝐪𝐮𝐢𝐬𝐢𝐭𝐞𝐬 𝐟𝐨𝐫 𝐌𝐢𝐠𝐫𝐚𝐭𝐢𝐨𝐧:

Two PVs (Old & New) and Two PVCs (Old & New)
Set the old PV’s Reclaim Policy to “Retain”

𝐓𝐰𝐨 𝐌𝐞𝐭𝐡𝐨𝐝𝐬 𝐭𝐨 𝐏𝐞𝐫𝐟𝐨𝐫𝐦 𝐌𝐢𝐠𝐫𝐚𝐭𝐢𝐨𝐧:

𝑂𝑝𝑡𝑖𝑜𝑛 1: Use the Old Data in a New Pod
Best if you just need a new Pod with existing data.
Steps:
Set PV Reclaim Policy to “Retain”
Delete the old Pod & PVC (but keep the PV!)
Edit the PV to remove the claimRef block (makes it available)
Create a new PVC
Create a new Pod and attach old-PV + new-PVC

𝑃𝑜𝑡𝑒𝑛𝑡𝑖𝑎𝑙 𝑅𝑖𝑠𝑘𝑠:
If you need a fresh PV with no old data, manually clean it before binding.
If the StorageClass differs, Kubernetes won’t auto-bind it.
If another pod is still using old-PV, conflicts might arise.
If old-PV is ReadWriteOnce (RWO), it cannot be mounted to multiple pods simultaneously.

𝑂𝑝𝑡𝑖𝑜𝑛 2: Migrate/Copy Data from Old-PV to New-PV
Best if you need a fresh PV with a new setup but want to retain old data.
Steps:
Set the old PV’s Reclaim Policy to “Retain”
Create a new PV & PVC
Create a temporary migration pod that copies data from old-PV → new-PV