Storage Type - Difference between Raids

Storage : We use Storage for fault tolerance of data to prevent loss prevention. 

We Use Raid (Redundant  Array of Independent disks) 

Type of Raids.  

1. Raid 0 
2. Raid 1 
3. Raid 5 
4. Raid 10  

Raid 0 : It’s not a fault Tolerance.  It does striping, it means it will divide the data to disks. It means your half data is present on disk 1 and other half is present on Disk 2. 

 

Pros : It is used because the data transfer is speed. 

Cons: If any of the disk fails, then your data is gone. 

RAID 1 : Does Mirroring and Duplexing. It is fault tolerant. 

Here data is copied on each disks. Even if any of the disk is failed. You will have backup. 

 

RAID 5 : Does Striping with Partity. 

It requires 3 or more disks. Most commonly used. It is Fast and can store large amount of data. 

Pros :  

It does striping on each disks and Parity as well.  Parity means, in case of any disaster the disks fails. Using Parity feature it will restore the data. 

Cons: 

Due to Partity option enabled on RAID 5, It will not let you use total amount of present on the disk. 

Ex : If you have total 4 TB disks. Then it will let you use only 3 TB of space for actual data.  

 

RAID 6 : It requires 4 or more disk. Does striping with Double Parity on all disks. 

Pros : In case of two disks fail at same time, no data will be lost. In this case, just replace the failed disks. Then Raid 6 will use Parity from other disks to rebuild the data on other drive. 

 

RAID 10 (1+0) : It means it is a combination of RAID 1 with RAID 0. 

It requires 4 disks. It will do striping (Raid 0) and does mirroring of data to on disks (Raid 1). 

 

Pros : Data transfer speed because of RAID 0 and Fault tolerance because of RAID 1. 

Cons : You can use only 50 % for datastore. It means you can use 2 TB only out of 4 TB.