MinIO Version Pinning and xl Meta Compatibility

Applies when: changing MinIO image tag, debugging MinIO startup failures, or resetting MinIO volumes.

MinIO does NOT support downgrades. Once data is written by a newer version, older versions cannot read it.
The xl meta version is a storage format version embedded in MinIO's data files. Version 3 was introduced in 2025 releases.
Previous pin RELEASE.2024-11-07T00-52-20Z could not read xl meta v3 data written by a latest pull.
Current pin: RELEASE.2025-09-07T16-13-09Z -- the last free release on Docker Hub before MinIO stopped publishing (Oct 2025).
curl was removed from MinIO Docker images after RELEASE.2023-10-25T06-33-25Z (UBI micro base). Healthcheck must use mc ready local instead of curl -f.
If MinIO volume data is truly unrecoverable (corrupted, not just version mismatch), the nuclear option is docker volume rm cpv3_minio -- but this destroys all stored media files.
MinIO GitHub repo was archived Feb 2026. Future images may need to come from alternative sources (alpine/minio, self-build).