ILM policy and storage configuration review

During decommissioning, information lifecycle management (ILM) re-evaluation migrates object data from the Storage Node being decommissioned. This involves the ILM re-evaluation process noting that the decommissioned Storage Node is no longer a valid content location, copying all object data that is currently located on that Storage Node to other Storage Nodes, and proceeding in a manner that satisfies the StorageGRID Webscale systemʹs ILM policy.

Before starting the decommissioning process, review the StorageGRID Webscale system’s ILM policy to understand where ILM re-evaluation will place copies of object data during decommissioning. Carefully consider where new copies will be made by reviewing ILM rules. The StorageGRID Webscale system must have enough capacity of the correct type and in the correct locations to accommodate both this copying of object data and the ongoing operations of the StorageGRID Webscale system.

Consider the following:
Note: An ILM policy that cannot be satisfied will lead to backlogs and alarms, and can halt operation of the StorageGRID Webscale system.

Verify that the proposed topology that will result from the decommissioning process satisfies the ILM policy by assessing the factors listed in the table.

Area to Assess Notes
Available capacity Will there be enough storage capacity in the StorageGRID Webscale system to accommodate all of the object data stored in the StorageGRID Webscale system, including the permanent copies of object data currently stored on the Storage Node to be decommissioned?

Will there be enough capacity to handle the anticipated growth in stored object data for a reasonable interval of time after decommissioning is complete?

Location of storage If enough capacity remains in the StorageGRID Webscale system as a whole, is the capacity in the right locations to satisfy the StorageGRID Webscale system’s business rules?
Storage type Will there be enough storage of the appropriate type after decommissioning is complete? For example, ILM rules might dictate that content be moved from SATA to SAS as content ages. If so, you must ensure that enough storage of the appropriate type is available in the final configuration of the StorageGRID Webscale system.