ALUA | Asynchronous Logical Unit Access. PowerStore uses implicit ALUA which allows PowerStore to provide a recommended active optimized path to a storage resource for the hosts. |
Asynchronous replication | A replication method that allows replicating data over long distances and maintaining a replica at a destination site. Updates to the destination image can be issued manually, or automatically based on a customizable RPO. |
Bandwidth | The amount of data, represented in MB/s, which can be transferred in a given period. |
Common base | A pair of snapshots that are taken on a replication source and destination storage resource that have the same point-in-time image. |
Destination storage resource | A storage resource that is used for disaster recovery in a replication session. This term is also known as a target image. |
Internal snapshot (replication snapshot) | The system creates unified snapshots and is part of an asynchronous replication session. These snapshots are only visible in the PowerStore CLI or PowerStore REST API, and manual modification is not possible. Each asynchronous replication session uses up to two internal snapshots that are taken on the source and destination storage resources. Each session also takes up one read/write snapshot on destination storage system. The last successful internal read-only (RO) snapshots for source and destination storage resources and are used as a common base. |
PowerStore Manager | A web-based management interface for creating storage resources and configuring and scheduling protection of stored data on PowerStore. PowerStore Manager can be used for all management of PowerStore native replication. |
PowerStore CLI | A tool that can be installed on an operating system to manage a PowerStore system. |
RecoverPoint for Virtual Machines | Protects virtual machines (VMs) in a VMware environment with VM-level granularity and provides local or remote replication for any point-in-time recovery. This feature is integrated with VMware vCenter and has integrated orchestration and automation capabilities. |
Recovery point objective (RPO) | Acceptable amount of data, which is measured in units of time, that may be lost due to a failure. For example, if a storage resource has a one-hour RPO, data that is written to the storage resource within the last hour may be lost when the replication session is failed over to the destination storage resource. |
Recovery time objective (RTO) | Duration of time in which a business process must be restored after a disaster. For example, an RTO of one hour requires restoring data access within one hour after a disaster occurs. |
Remote systems | Relationship that is configured between two PowerStore systems. |
Replication session | A relationship that is configured between two storage resources of the same type on different systems, and automatically synchronizes data from one resource to another. |
Snapshot | Also called a unified snapshot, a snapshot is a point-in-time view of a storage resource. When a snapshot is taken, it creates an exact copy of the source storage resource and shares all blocks of data with it. As data changes on the source, new blocks are allocated and written to. Unified snapshot technology can be used to take a snapshot of a block or file storage resource. |
Storage resource | A top-level object that a user can provision, which is associated with a specific quantity of storage. All host access and data-protection activities are performed at this level. In this document, storage resources refer to resources that support replication such as volumes, volume groups, and thin clones. |
Synchronous Replication | A replication method to keep the source and destination of a replication system consistent (zero RPO). PowerStore supports active-active synchronous replication with metro active-active replication and active-passive synchronous replication: Active-active – bi-directional synchronization where either mirrored volume can accept host IO (metro). Supports transparent failover. Active-passive – unidirectional synchronous replication where only the source volume accepts host IO. An external triggered failover (such as by cluster software) is required to enable the volume on destination and for re-protection. In both configurations, data is only acknowledged to the hosts when data has been acknowledged by the active site and the replication destination. |
Thin clone | A read/write copy of a volume, volume group, file system, NAS server, or snapshot that shares blocks with the parent resource. |
Unisphere Manager for RecoverPoint | A web-based interface for managing RecoverPoint replication. It serves as a single pane of glass for replicating storage resources of multiple storage systems that are configured to use RecoverPoint. Consistency groups are created, replicated, and recovered through this interface. |
User snapshot | A snapshot that is created manually by the user or by a protection policy with an associated snapshot rule. This snapshot type is different than an internal snapshot, which is taken automatically by the system with asynchronous replication. |
Volume | A block-based storage resource that a user provisions. It represents a SCSI logical unit. |
Volume group | A storage instance that contains one or more volumes within a storage system. Volume groups can be configured with write-order consistency and help organize the storage that is allocated for particular hosts. |
