RAID

RAID - Redundant Array of Independent Disks

Raid Types : 
1) Hardware  External RAID Controller Card or Internal RAID on chip
2) Software ; Software only ( susceptible to boot errors)  or Hybrid ( user hardware component to deliver RAID BIOS functions ) 

RAID Levels 

RAID 0 - Disk Stripping ( no redundancy, higher read/write throughput  ) 
RAID 1 - Disk Mirroring ( redundancy, handles single disk failure, increased read performance, uses more space capacity ) 
RAID 5 - Stripping With Parity ( redundancy, can withstand single disk failure , increased read performance, takes lot more space.
RAID 6 - Stripping with Double Parity ( minimum four disks needed, can withstand double disk failure , higher redundancy and increased read performance)
RAID 10 - RAID 0 of RAID1's ( minimum four disks needed 

RAID protects data availability and redundancy, but does not recognize or remediate file corruption, write errors, or hacking. Not a replacement for backup

Nice articles on RAIDs. 


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