PowerScale OneFS 9.8.0.0 Web Administration Guide

Storage pool functions

When a cluster is installed, and whenever nodes are added to the cluster, OneFS automatically groups nodes into node pools. Autoprovisioning of nodes into node pools enables OneFS to optimize performance, reliability, and data protection on the cluster.

OneFS uses specific criteria to determine how, or whether, to group nodes into node pools. Nodes are compatible if there are no restrictions between them, or if existing restrictions can be overridden ("soft restrictions"). Nodes are equivalent if no restrictions exist between them. Nodes are automatically provisioned together only if they are equivalent. If nodes are compatible but not equivalent, you can manually move them into the same node pool.

Without an active SmartPools license, OneFS applies a default file pool policy to organize all data into a single file pool. With this policy, OneFS distributes data across the entire cluster so that data is protected and readily accessible. When you activate a SmartPools license, additional functions become available.

OneFS provides the following functions, with or without an active SmartPools license:

Autoprovisioning of node pools

Automatically groups equivalent nodes into node pools for optimal storage efficiency and protection. At least three equivalent nodes are required for autoprovisioning to work.

Tiers

Groups node pools into logical tiers of storage. If you activate a SmartPools license for this feature, you can create custom file pool policies and direct different file pools to appropriate storage tiers.

Default file pool policy

Governs all file types and can store files anywhere on the cluster. Custom file pool policies, which require a SmartPools license, take precedence over the default file pool policy.

Requested protection

Specifies a requested protection setting for the default file pool, per node pool, or even on individual files. You can leave the default setting in place, or choose the suggested protection calculated by OneFS for optimal data protection.

Virtual hot spare

Reserves a portion of available storage space for data repair in the event of a disk failure.

SSD strategies

Defines the type of data that is stored on SSDs in the cluster. For example, storing metadata for read/write acceleration.

L3 cache

Specifies that SSDs in nodes are used to increase cache memory and speed up file system performance across larger working file sets.

Global namespace acceleration

Activates global namespace acceleration (GNA), which enables data stored on node pools without SSDs to access SSDs elsewhere in the cluster to store extra metadata mirrors. Extra metadata mirrors accelerate metadata read operations.

When you activate a SmartPools license, OneFS provides the following additional functions:

Custom file pool policies

Creates custom file pool policies to identify different classes of files, and stores these file pools in logical storage tiers. For example, you can define a high-performance tier of node pools and an archival tier of high-capacity node pools. Then, with custom file pool policies, you can identify file pools based on matching criteria, and you can define actions to perform on these pools. For example, one file pool policy can identify all JPEG files older than a year and store them in an archival tier. Another policy can move all files that were created or modified within the last three months to a performance tier.

Storage pool spillover

Enables automated capacity overflow management for storage pools. Spillover defines how to handle write operations when a storage pool is not writable. If spillover is enabled, data is redirected to a specified storage pool. If spillover is disabled, new data writes fail and an error message is sent to the client that is attempting the write operation.