How HCP uses the information found in service plans

If the service plan for a given namespace defines only the ingest tier, for each object in that namespace, the protection service works to ensure that:

The correct number of copies of the object data are always stored on the ingest tier, which can be primary running storage or economy storage.

The correct number of copies of the object metadata are always stored on primary running storage.

For details on how the protection service works, see Protection service.

If the service plan for a given namespace defines multiple storage tiers, the storage tiering service works to ensure that each object in that namespace is stored on the correct tier and the correct number of copies of the object is stored on each tier.

For each object in that namespace, the storage tiering service:

Moves copies of the object data among the storage tiers that are defined for the namespace to satisfy the transition criteria that are defined for each storage tier

Upon moving all existing copies of the data for an object from one tier to another:

oIf the new tier has a different DPL than the previous tier, creates or deletes the number of copies of object data that’s required to satisfy the DPL setting for the new tier

oIf the new tier has a different primary running storage metadata protection level (MPL) than the previous tier, creates or deletes the number of copies of object metadata that’s required to satisfy the MPL setting for the new tier

Upon moving a replicated object to a metadata-only tier, deletes all copies of the object data from the previous tier, and if the previous tier is not the ingest tier, deletes any copies of the object data that exist on the ingest tier (primary running storage or economy storage)

Checks to see if the object data has been read from a data storage tier for which rehydration is enabled, and if so, creates an extra copy of the object data on the ingest tier

After moving a replicated object to a metadata-only tier for which rehydration is enabled and making that object metadata-only, checks to see whether that object has been read from a remote system, and if so, restores the data to each copy of the object that’s stored on the ingest tier (primary running storage or economy storage)

For information about how the storage tiering service works, see Storage tiering service.

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