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Determining the overall disk capacity requirement is a relatively straightforward process. The objective of this process is to calculate the amount of disk space necessary to provide sufficient disk capacity to all expected users over the period of time that will be covered by the initial acquisition period—that is, how long before a capacity expansion adds more disk space to provide home-directory storage. If the PowerScale storage cluster undergoes a capacity expansion once per year, then the initial node acquisition needs to provide sufficient disk capacity to last for the entire year.
The following sizing factors are necessary to accurately estimate the amount of disk capacity necessary for home-directory storage on a PowerScale storage cluster.
Once this information is known, a PowerScale technical consultant can determine the total amount of storage space required for home directory data, as well as the specific node type and configuration necessary to satisfy the capacity requirement.
To help enterprises maximize the long-term value of their critical business data and drive down storage management cost and complexity, PowerScale offers SmartQuotas: a simple, scalable and flexible quota management and provisioning software application that integrates with the Dell EMC PowerScale OneFS operating system.
SmartQuotas allows administrators to control and limit storage usage across their organization and provision a single pool of PowerScale clustered storage to best meet their unique storage challenges.
A quota by definition is the permissible share or proportional part of a total. Applied to storage requirements, it is the amount of storage capacity that is permissible to a certain entity within the PowerScale cluster. At its core, a quota system is a combination of accounting, enforcement and reporting. Accounting refers to tracking data owned by resource entities, such as users, groups and directories. ‘Enforcement’ refers to setting and forcing limits for certain counts. ‘Reporting’ refers to the mechanism by which such enforcement can be conveyed to the administrators or users.
To apply SmartQuotas, two types of capacity quotas need to be considered: Accounting Quotas and Enforcement Quotas.
Accounting quotas monitor but do not limit disk storage utilization, are useful for auditing, planning, or billing purposes. Using Accounting quotas enables the following capabilities:
Enforcement quotas on the other hand include all of the functionality of the accounting option plus the ability to limit disk storage and send notification. Using enforcement limits, you can logically partition a cluster to control or restrict how much storage that a user, group, or directory can use. There are four types of enforcement quotas:
More information on SmartQuotas, including detailed planning and management information, is available in the Storage Quota Management and Provisioning with Dell EMC PowerScale SmartQuotas white paper.
To effectively protect a file system that is hundreds of terabytes or petabytes in size requires an extensive use of multiple data availability and data protection technologies. As the demand for storage is continuing to grow exponentially the demand for ways to protect and manage that storage also increases.
Historically, data protection was always synonymous with tape backup. However, over the past decade, several technologies such as replication, synchronization, and data snapshots have become mainstream. Snapshots offer rapid, user-driven restores without the need for administrative assistance.
OneFS snapshots are highly scalable and typically take less than one second to create. They create little performance overhead, regardless of the level of file-system activity, the size of the file system, or the size of the directory being copied. Also, only the changed blocks of a file are stored when updating the snapshots, thereby ensuring highly-efficient snapshot storage utilization. User access to the available snapshots is via a .snapshot hidden directory under each file system directory.
PowerScale SnapshotIQ software can also be used to create unlimited snapshots on a cluster. This provides a substantial benefit over the majority of other snapshot implementations because the snapshot intervals can be far more granular and hence offer improved recovery point objective (RPO) time frames. SnapshotIQ can take read-only, point-in-time copies of any directory or subdirectory within OneFS, providing the following benefits:
More information on SnapshotIQ is available in Data Protection with Dell EMC PowerScale SnapshotIQ white paper.