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The legacy PowerFlex block API is hosted as a microservice in PFMP. The data model for this API is structurally the same as in versions before v4.x. When users issue block API calls to the PFMP cluster, an ingress microservice redirects the request to one of the Meta Data Manager services. The gateway connects to the Meta Data Manager (MDM) in the PowerFlex deployment. The MDM is a tightly coupled cluster that coordinates activities in the PowerFlex system. It is the brain of the PowerFlex system in that it monitors the system, coordinates rebalance operations and rebuilds, and coordinates changes to the storage configuration.
The PowerFlex gateway formats the response from the MDM in a RESTful manner and returns it to the API client. The API consumes and produces configuration details in JSON format (application/json).
The URLs are organized into two categories.
The /api/types URL applies to all instances for the given type. For example, GET /api/types/Sds/instances will return all instances of “type” SDS. The /api/instances URL will act on a specific object of the type specified in the URL. The ID of the object is typically a required part of the URL.
For example, /api/instances/StoragePool::{StoragePoolID} will return information for the storage pool ID specified in the URL.