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Anil Kumar
Anil Kumar

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๐—Ÿ๐—ฒ๐˜'๐˜€ ๐—ง๐—ฎ๐—น๐—ธ ๐—”๐—ฏ๐—ผ๐˜‚๐˜ ๐—ฃ๐—ฉ ๐— ๐—ถ๐—ด๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป!๐Ÿš€

๐—›๐—ฒ๐—น๐—น๐—ผ ๐—–๐—น๐—ผ๐˜‚๐—ฑ๐—ฒ๐—ฒ๐˜€ โ˜๏ธ!

๐—Ÿ๐—ฒ๐˜'๐˜€ ๐—ง๐—ฎ๐—น๐—ธ ๐—”๐—ฏ๐—ผ๐˜‚๐˜ ๐—ฃ๐—ฉ ๐— ๐—ถ๐—ด๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป!
๐Ÿ‘จโ€๐Ÿ’ป ๐€๐ง๐ข๐ฅ: Hey Rakhul! Have you ever faced a challenge where you needed to upgrade storage, migrate to a different provider, or change storage classes?
๐Ÿ‘จโ€๐Ÿ’ป ๐‘๐š๐ค๐ก๐ฎ๐ฅ: Yes, Anil! But honestly, I have no idea how to do it. Can you guide me?
๐Ÿ‘จโ€๐Ÿซ ๐€๐ง๐ข๐ฅ: Of course! No worries, Iโ€™ll explain it in a simple way. Letโ€™s dive in! ๐Ÿ”ฅ


๐Ÿ”„ ๐–๐ก๐ฒ ๐ƒ๐จ ๐–๐ž ๐๐ž๐ž๐ ๐ญ๐จ ๐Œ๐ข๐ ๐ซ๐š๐ญ๐ž ๐ƒ๐š๐ญ๐š ๐Ÿ๐ซ๐จ๐ฆ ๐Ž๐ง๐ž ๐๐• ๐ญ๐จ ๐€๐ง๐จ๐ญ๐ก๐ž๐ซ?
๐Ÿ”น Upgrading Storage Classes โ€“ Moving from an old, slower storage class (standard) to a new, faster one (ssd).
๐Ÿ”น Switching Cloud Providers โ€“ Migrating from AWS EBS โ†’ Google Persistent Disk or any other provider.
๐Ÿ”น Scaling Storage โ€“ If your PV is full and cannot be resized, you need a bigger PV.
๐Ÿ”น Stateful Application Upgrades โ€“ Moving a MySQL database or other persistent apps to a new PV.
๐Ÿ”น Backups & Disaster Recovery โ€“ Keeping data safe from accidental deletion, corruption, or failures.


โšก ๐๐ซ๐ž-๐‘๐ž๐ช๐ฎ๐ข๐ฌ๐ข๐ญ๐ž๐ฌ ๐Ÿ๐จ๐ซ ๐Œ๐ข๐ ๐ซ๐š๐ญ๐ข๐จ๐ง:

โœ… Two PVs (Old & New) and Two PVCs (Old & New)
โœ… Set the old PV's Reclaim Policy to "Retain"


๐Ÿ”ฅ ๐“๐ฐ๐จ ๐Œ๐ž๐ญ๐ก๐จ๐๐ฌ ๐ญ๐จ ๐๐ž๐ซ๐Ÿ๐จ๐ซ๐ฆ ๐Œ๐ข๐ ๐ซ๐š๐ญ๐ข๐จ๐ง:

๐Ÿ…ฐ๏ธ ๐‘‚๐‘๐‘ก๐‘–๐‘œ๐‘› 1: Use the Old Data in a New Pod
Best if you just need a new Pod with existing data.
Steps:
โœ… Set PV Reclaim Policy to "Retain"
โœ… Delete the old Pod & PVC (but keep the PV!)
โœ… Edit the PV to remove the claimRef block (makes it available)
โœ… Create a new PVC
โœ… Create a new Pod and attach old-PV + new-PVC

โš ๏ธ ๐‘ƒ๐‘œ๐‘ก๐‘’๐‘›๐‘ก๐‘–๐‘Ž๐‘™ ๐‘…๐‘–๐‘ ๐‘˜๐‘ :
โ— If you need a fresh PV with no old data, manually clean it before binding.
โ— If the StorageClass differs, Kubernetes wonโ€™t auto-bind it.
โ— If another pod is still using old-PV, conflicts might arise.
โ— If old-PV is ReadWriteOnce (RWO), it cannot be mounted to multiple pods simultaneously.


๐Ÿ…ฑ๏ธ ๐‘‚๐‘๐‘ก๐‘–๐‘œ๐‘› 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:
โœ… Set the old PVโ€™s Reclaim Policy to "Retain"
โœ… Create a new PV & PVC
โœ… Create a temporary migration pod that copies data from old-PV โ†’ new-PV

๐Ÿ“Œ ๐ต๐‘œ๐‘›๐‘ข๐‘ : Iโ€™ve attached a detailed code snippet and workflow in the image below! Check it out! ๐Ÿš€

๐Ÿ‘จโ€๐Ÿ’ป ๐‘๐š๐ค๐ก๐ฎ๐ฅ: Wow, that makes so much sense! Iโ€™ll start working on it right away. Thanks, Anil! ๐Ÿ˜ƒ


๐Ÿ”ฝ Whatโ€™s Your Experience with PV Migration? ๐Ÿ”ฝ
๐Ÿ’ฌ Drop your thoughts & questions in the comments! Letโ€™s discuss. ๐Ÿ‘‡๐Ÿ”ฅ

CloudComputing #Kubernetes #K8s #Containers #DevOps #CloudNative

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