• Optimal supported aggregated throughput rates:– 3 Terabytes per hour (TB/hr) for passthrough write operations– 4 TB/hr for optimized write operationsNOTE: Passthrough writes are when data is sent from a media server to the DR Series systemwithout applying any optimization to the data. By contrast, optimized writes are when data is sentfrom a media server to the DR Series system after optimization is applied to the data.• Supported OST operations– Backup (Passthrough writes and Optimized writes)– Restore– ReplicationNOTE: To check for the latest supported OST software components and operating guidelines, see theDell DRSeries System Interoperability Guide. This document is available at support.dell.com/manuals.DR Series System and Data OperationsData is stored and resides on the Dell DR Series system, a two-rack unit (RU) appliance, which comes preinstalled withthe system software. Starting with the 2.0 release. the DR Series system comes in two types:• DR4000 system: this consists of preinstalled DR4000 system software on a Dell R510 appliance platform.• DR4100 system: this consists of preinstalled DR4000 system software on a Dell R720xd appliance platform.The DR Series system consists of a total of 14 drives. Two of these drives are 2.5–inch drives that are configured as aRedundant Array of Independent Disks (RAID) 1 on the RAID Controller and this is considered to be volume 1. In theDR4000 system, these drives are internal, while in the DR4100 system, these drives are accessible from the rear. Thedata that is being backed up is stored on the 12 virtual disks that reside on the DR Series system appliance. This releasealso supported additional storage in the form of external expansion shelf enclosures (see theDR Series Expansion Shelfsection in this topic). The hot-swappable data drives that are attached to the RAID controller are configured as:• 11 drives that operate as RAID 6, which act as virtual-disks for data storage (drives 1–11).• The remaining drive (drive 0) acts as the dedicated hot-spare drive for RAID 6 for the system.The DR Series system supports RAID 6, which allows the appliance to continue read and write requests to the RAIDarray virtual disks even in the event of up to two concurrent disk failures, providing protection to your mission-criticaldata. In this way, the system design supports double-data drive failure survivability.If the system detects that one of the 11 virtual drives has failed, then the dedicated hot spare (drive slot 0) becomes anactive member of the RAID group. Data is then automatically copied to the hot spare as it acts as the replacement forthe failed drive. The dedicated hot spare remains inactive until it is called upon to replaced a failed drive. This scenariois usually encountered when a faulty data drive is replaced. The hot spare can act as replacement for both internalmirrored drives and the RAID 6 drive arrays.Figure 1. DR4000/DR4100 System Drive Slot Locations26
