RAID Tips 1 of 10 - Requirements

By Geek -
When you are about to build a RAID, make sure you understand your storage requirements. The following points are significant
  • Array capacity. Whatever your capacity requirements are, these are underestimated, most likely by the factor of two.
  • Budget limits.
  • Expected activity profile, especially read-to-write ratio. If there are mostly reads and few writes, then RAID 5 or RAID 6 would be OK. If significant random write activity is expected, consider RAID 10 instead.
  • Expected lifetime. Whatever the projected lifetime of the storage system is, it is underestimated.

For a quick estimation of capacities for various RAID levels, check the online RAID calculator.

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