A records app should run with a read-only root filesystem but still…

Question

A records app should run with a read-only root filesystem but still needs a writable cache directory. What configuration satisfies both?

Accepted Answer

Set readOnlyRootFilesystem: true and mount an emptyDir volume at the cache path. — Lock the house (read-only root) but leave a scratch notepad (emptyDir) where the app is allowed to scribble. That gives immutability without breaking cache writes. Privileged remounts or writing into image layers miss the point.

Answer

Set privileged: true so the root filesystem can be remounted read-write at runtime.

Answer

Set readOnlyRootFilesystem: true and write cache files into the image layers permanently.

Answer

Disable the root filesystem entirely and store all files only in ConfigMap keys.

A records app should run with a read-only root filesystem but still needs a writable cache directory. What configuration satisfies both?

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