Overview of RAID for IP Video Storage

 Storage is a big part of IP video security and so I thought I would start a small series of video storage starting with the basics.  Today we will discuss RAID.  RAID has been discussed many (x4) times throughout the years but I still get questions...


 


RAID 50:
RAID 50 combines the block striping and parity of RAID 5 with the straight block striping of RAID 0 and requires a minimum of 6 drives.  In essence it takes the data of multiple RAID 5 sets and then stripes it across all drives.   Adding RAID 0 to multiple RAID 5 sets allows you to increase the write performance of a straight RAID 5 set as well as increase the level of fault tolerance.  A RAID 50 can lose as many drives as there are individual RAID 5 sets.

Tip: You can estimate a RAID 50 array’s usable capacity by this simple equation, [R *(n-1)]*s = U.  Where R is the raw capacity of one hard drive, n is the number of hard drives in a single RAID 5 array, s is the number of RAID 5 arrays being striped and U is the usable capacity of the array.
 


RAID 60:
RAID 60 is similar to RAID 50 except it combines the straight block-level striping of RAID 0 with the distributed double parity of RAID 6. That is, a RAID 0 array striped across RAID 6 elements. It requires at least 8 disks.

Tip: You can estimate a RAID 50 array’s usable capacity by this simple equation, [R *(n-2)]*s = U.  Where R is the raw capacity of one hard drive, n is the number of hard drives in a single RAID 5 array, s is the number of RAID 5 arrays being striped and U is the usable capacity of the array.