Nearline SAS Disks

Nearline SAS disks are high capacity cost effective disks for data backup and archive use. Nearline SAS disks can store information that requires a low access rate at a reasonable speed more cost effectively than SAS disks.

Caution

  • Nearline SAS disks are used to store data that does not need the access performance of SAS disks. They are far more cost effective than SAS disks. It is recommended that SAS disks be used for data that is constantly accessed or when high performance/reliability is required.

  • If the ambient temperature exceeds the operating environment conditions, Nearline SAS disk performance may be reduced.

  • Nearline SAS disks can be used as Advanced Copy destinations and for the storage of archived data.

  • When Nearline SAS disks are used as an Advanced Copy destination, delayed access responses and slower copy speeds may be noticed, depending on the amount of I/O and the number of copy sessions.

  • The following disks are Advanced Format (512e) disks.

    • 3.5" Nearline SAS disks (8TB)

    • 3.5" Nearline SAS disks (12TB)

    • 3.5" Nearline SAS disks (18TB)

    • 3.5" Nearline SAS self encrypting disks (8TB)

    • 3.5" Nearline SAS self encrypting disks (16TB)

  • When using Advanced Format (512e) disks, make sure that Advanced Format (512e) is supported by the server OS and the applications. If the server OS and applications do not support Advanced Format (512e), random write performance may be reduced.

  • For details on the RAID levels that can be configured with Nearline SAS disks that have 8TB or more, refer to Supported RAID.

The drive characteristics of NVMe SSDs, SAS SSDs, SAS disks, and Nearline SAS disks are shown below.

Table: Drive Characteristics

Type

Reliability

Performance

Price (*1)

NVMe SSDs

◎

◎

△

SAS SSDs

◎

◎

△

SAS disks

¡

¡

¡

Nearline SAS disks

△

△

◎

◎: Very good ¡: Good △: Reasonable

*1 : 

Bits are used to compare the prices for each drive type and the price goes up in the following order: ◎ < ¡ < △.

For more details on the characteristics of NVMe SSDs and SAS SSDs, refer to Table: SSD Characteristics and Specification Differences.