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The following table provides definitions for some of the terms that are used in this document:
Term | Definition |
Consistency group | An SRDF consistency group is a composite group comprised of SRDF devices with consistency enabled. The devices in the consistency group are configured to act in unison to maintain the integrity of a database and ensures consistency when distributed across multiple arrays or across multiple devices within an array. SRDF consistency group protection is available for SRDF/S and SRDF/A. |
Composite group | A user-defined group of device members that can span multiple PowerMax storage systems and SRDF groups. |
Device group* | A user-defined group consisting of a set of devices used for (local or remote) replication purposes. At the time of writing, a device group must be defined as type REGULAR, SRDF1, or SRDF2 and may contain various device lists for standard, clones, snapshots, and remote devices. If the SRDF group type is defined as SRDF1 or SRDF2, the group is considered an SRDF device group. |
SAP HANA hardware and cloud measurement tool (HCMT) | An SAP tool used for the certification process. The tool measures the storage and network performance of an SAP HANA hardware configuration that must fulfill a set of SAP KPIs. |
Key performance indicator (KPI) | A threshold that must be achieved or fulfilled in a test. |
Recovery point objective (RPO) | The maximum time span of data loss that is acceptable in a disaster situation. |
Recovery time objective (RTO) | The maximum time that is allowed for a secondary or standby system to become available. |
Remote Data Facility (SRDF) group | A user-defined object that provides a collective data transfer path linking devices of two separate systems. An SRDF group enables synchronization of data between the R1 (primary) and R2 (secondary) volume pairs that are associated with the group. At least one physical connection must exist between the two systems in the fabric topology. |
SAP HANA standby host | A passive host in an SAP HANA system. The standby host has all services started but does not accept SQL requests. It waits for the failure of another host and then takes over the persistency and becomes active. |
SAP HANA worker host | A host that is active in an SAP HANA system—that is, one that is accepting SQL requests. |
Scale-out system | An SAP HANA system that consists of more than a single host. |
Scale-up system | An SAP HANA system that consists of exactly one host. |
<sid>adm | The administrator user ID of the SAP HANA database. <sid> represents a three-character system ID. |
Storage group | A logical grouping of thin devices. LUN addresses are assigned to the devices in the storage group when the view is created if the group is either cascaded or stand-alone. Often, there is a correlation between a storage group and a host application. One or more storage groups may be assigned to an application to simplify management of the system. Storage groups can also be shared among applications. |
Symmetrix Remote Data Facility (SRDF) consistency group | A composite group of SRDF devices (SRDF1 or SRDF2) that has been enabled for remote database consistency. The SRDF consistency groups operate in unison to preserve the integrity and dependent-write consistency of a database that is distributed across multiple arrays. |
Tailored Data Center Integration (TDI) | An SAP hardware-partner program for certification of hardware components. See the Certified and Supported SAP HANA Hardware Directory.
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Note: Consistency groups and device groups are available through the CLI only. These groups are not available or operable in Unisphere. Unisphere SRDF replication is entirely Storage Group (SG)-based.