Use this screen to select the RAID level.
RAID 10 maintains a full copy of the data. RAID 10 uses data redundancy to ensure data accessibility in case of a disk failure. The storage overhead is 2n where n is the number of disks. For example, 1GB of data will consume 2GB of storage.
RAID 5 uses rotating parity. The storage overhead is 1/n where n is the number of disks. If there are 5 disks, the storage overhead is 20%, meaning 1GB of data consumes 1.2GB of storage. To change the RAID 5 stripe size or parity stripe count, select Administration>System Defaults>Volumes-Static.
For volumes using RAID 10 or 5, the system automatically detects disk failures and rebuilds the data using a hot spare.
Recommendations
RAID 5 or 10 is strongly recommended for most production environments. If there is a disk failure, these levels provide continuous access to data.
RAID 10 is recommended for optimal performance.
For additional full copies (mirrors) of the data, select Administration>System Defaults>Volumes-Static. To change the threshold setting to automatically expand the storage pool, select Administration>Configure System Defaults>Volumes-Dynamic.
RAID 5 is recommended to minimize the overhead for parity data.