raid

Question

Answer

Why can storage devices like HDDs and SSDs fail?

Due to moving parts

How is redundancy achieved with RAID?

By combining multiple drives to protect data if one fails

Is RAID a backup solution?

No

What does RAID stand for?

Redundant Array of Independent Disks (or Inexpensive Disks)

How many drives does RAID 0 require at minimum?

At least two

What does RAID 0 do with data?

Splits (stripes) it across all drives

What is an advantage of RAID 0?

Improves read/write speeds by distributing data across multiple drives

What is a disadvantage of RAID 0?

No redundancy; if one drive fails

Why is RAID 0 sometimes called "zero redundancy"?

Because it provides no fault tolerance

How many drives does RAID 1 require at minimum?

At least two

What does RAID 1 do with data?

Duplicates (mirrors) it across all drives

What is an advantage of RAID 1?

Full redundancy; data remains accessible if one drive fails

What is a disadvantage of RAID 1?

Requires double the storage capacity

Why is RAID 1 write speed slower than RAID 0?

Because of data duplication

How many drives does RAID 5 require at minimum?

At least three

What does RAID 5 do with data?

Stripes data across drives with parity distributed across all drives

What is an advantage of RAID 5?

Redundancy; data can be reconstructed using parity if one drive fails

How storage-efficient is RAID 5 compared to RAID 1?

More efficient

What is a disadvantage of RAID 5?

Performance overhead during recovery due to parity calculations

How many drive failures can RAID 5 tolerate?

One

How many drives does RAID 6 require at minimum?

At least four

How does RAID 6 differ from RAID 5?

It includes two parity blocks distributed across drives instead of one

How many drive failures can RAID 6 tolerate?

Two

What is a disadvantage of RAID 6?

Requires an additional drive for parity

How many drives does RAID 10 require at minimum?

At least four

What two RAID levels does RAID 10 combine?

RAID 1 (mirroring) and RAID 0 (striping)

How is RAID 10 structured?

Drives are mirrored in pairs

What is an advantage of RAID 10?

High performance from striping and redundancy from mirroring

What is a disadvantage of RAID 10?

Requires double the storage capacity

What does RAID 0 offer in terms of performance and redundancy?

High performance but no redundancy

What does RAID 1 offer in terms of performance and redundancy?

Full redundancy but high storage cost

What does RAID 5 offer in terms of performance and redundancy?

Single-drive redundancy and storage efficiency

What does RAID 6 offer in terms of performance and redundancy?

Two-drive redundancy with higher overhead

What does RAID 10 offer in terms of performance and redundancy?

High performance and redundancy but high storage cost