Storage tier properties specified in service plans

For each storage tier, including the ingest tier, that’s defined for a given namespace, the service plan specifies:

The storage pools that are used to store copies of each object on the tier. Each storage pool consists of one or more storage components. Each storage component represents a type of primary storage (running or spindown), economy storage device, an extended storage device, or a cloud storage service endpoint.

For each object that’s stored on the tier, the number of copies of the object data (called the data protection level, or DPL) that HCP must maintain on each storage pool and the number of copies of object metadata (called the metadata protection level or MPL) that HCP must maintain on the ingest tier.

The transition criteria for each tier except for the ingest tier. The transition criteria for a storage tier are the rules that determine when one or more copies of each object in the namespace must be stored on the tier:

oThe object age (number of days since ingest) at which one or more copies of the object data must be moved from the previous tier onto this tier

oFor service plans that define exactly two tiers, including the ingest tier, whether a threshold will be applied to the second tier, and if so, the percentage of ingest tier storage capacity that must be used (the threshold) before object data can be moved to the second storage tier

For a namespace that’s currently being replicated to another system, whether the copies of the object that are stored on the tier are to be made metadata-only.

Regardless of the transition criteria that are specified for a metadata-only tier, objects are moved to such a tier only after they are replicated. When a replicated object is moved to a metadata-only tier, all existing copies of the object data are deleted from the its current tier and the ingest tier, and HCP stores the specified number of copies of the object metadata on primary running storage.

Whether the data for each object stored on the tier is rehydrated (that is, restored on the ingest tier) upon being read from the tier, and if so, the number of days HCP is required to keep a rehydrated copy of object data on the ingest tier

Clicking on this button also submits any changes you’ve made to the external storage volumes in the storage pool.

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