Recommended RAID configurations
RAID devices must be configured in pairs. Hewlett Packard Enterprise recommends the following
configurations:
• SSD drives: two pairs of six drives in RAID 5
• SFF 10K SAS drives: two pairs of six drives in RAID 5
• LFF 7.2K drives: two pairs of six or 12 drives in RAID 6
Disk drive sizes and types
The HPE StoreVirtual 3200 Storage system configuration should include disk drives of the same size and
performance capability. When different drive types are installed in an enclosure, the usable capacity and
the processing ability of the entire storage system is affected. For example, if the storage system includes
different-sized drives, the storage system will default to the smallest individual drive size, and capacity in
the larger drives goes unused.
Here are some other considerations to consider when planning the disk drive configuration:
• All enclosures must have an equal number of drives or one less than the enclosure with the most disk
drives.
• A single enclosure can contain a mixture of HDD and SSD drives.
Spare disks
Spares are disks that are not active members of any particular array, but have been configured to be used
when a disk in one of the enclosures fails. If a spare is present, it will immediately be used to begin
rebuilding the information that was on the failed disk, using parity information from the other member
disks. During the rebuilding process, the array is operating in a reduced state and, unless it is a RAID6 or
RAID1+0 array, it cannot tolerate another disk failure in the same array. If another disk fails at this time,
the array becomes inaccessible and information stored there must be restored from backup.
After the rebuild of the data onto the spare is completed, when a replacement drive is inserted to replace
the failed drive, the system will automatically transfer the data from the spare onto the replacement drive
and return the spare to an available-spare state. It is important to note that the process of rebuilding the
spare or the replacement drive must not be interrupted or the process will be aborted.
Some administrators choose to configure multiple spare disks, so that multiple arrays can experience
failure and successfully recover before administrative intervention is required to replace the spare or
failed disk. When assigning a spare to an array, the administrator chooses which arrays and how many
arrays are protected by that spare.
Storage system sizing
As a general rule, the greater the number of drives that are included in the storage system, the greater
the performance level that can be achieved. However, performance considerations are offset by fault
tolerance considerations. You must strike a balance between performance and fault tolerance.
Preparing the site
Consider the following when preparing the site for the StoreVirtual 3200 Storage system. To ensure
continuous, safe, and reliable operation the storage system, install your system in an approved
environment.
•
Network infrastructure
Disk drive sizes and types
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