Memo on RAID

What is RAID? RAID, abbreviation for redundant array of independent disks, is a technology to manage disk IO in multiple disks. (more accurate and detail version of definition is at Wiki (https://en.wikipedia.org/wiki/Standard_RAID_levels).

RAID has few different types and called RAID 0, 1, 2, 3, 4, 5, 6.

It’s not like I did background check on facts, but I hear, the most popular types are RAID 0 and 5 today.

RAID 0 evenly distribute data across n number disks.  It’s simple straightforward way to take advantage of adding multiple disks.  The risk, if one of the disk goes wrong, then it’s all gone.

RAID 5 distribute data across n number disks randomly, plus parity information on one of the disk, so if one of the disk is damaged, you can recover like nothing happened.

Next I will organize pros, cons, and theological speed of each RAID.

Leave a Reply