RAID 0, 1, 5, 6, 10 Explained: How To Choose The Right RAID Level For Your Servers

You’re setting up a new server or upgrading storage, and suddenly you’re staring at a list of RAID levels like it’s a restaurant menu in another language. RAID 0? RAID 10? Hardware RAID vs software RAID?
This guide walks through RAID levels 0, 1, 5, 6, and 10 in plain language, so you can match each RAID level to real-world server hosting needs.
By the end, you’ll know which RAID setup gives you the best balance of speed, redundancy, and cost for web hosting, database servers, and other critical workloads.

What Is RAID Storage?

RAID (Redundant Array of Independent Disks) is just a fancy way of saying: “let’s make several drives behave like one smarter, safer drive.”

Instead of putting all your data on a single disk and praying it never dies, RAID spreads data across multiple disks to:

• Improve performance (faster reads and writes)

• Add redundancy (so one failed drive doesn’t take down everything)

• Keep services online longer (better uptime for hosting and databases)

But one important thing: RAID is not a backup.
It won’t save you from accidental deletes, malware, or someone dropping a whole server rack. RAID keeps services running when a drive dies; backups bring data back when life goes wrong.

When people talk about RAID, a few keywords show up a lot:

• Striping – splitting data into chunks and spreading it across drives (for speed)

• Mirroring – copying the same data to more than one drive (for safety)

• Parity – storing extra “check data” so the system can rebuild lost information

Different RAID levels mix these ideas in different ways.

Software RAID vs Hardware RAID

Before picking a RAID level, you also have to decide how you’ll run it: software RAID or hardware RAID.

Software RAID

Software RAID is handled by the operating system. No fancy card needed.

• Good when budget is tight

• Works fine for many small to mid-size setups

• Uses CPU resources for RAID calculations

• Depends on the OS (and its drivers) to behave

On a light-load server, software RAID is often “good enough.” On a busy hosting node or database server, those extra CPU cycles can start to matter.

Hardware RAID

Hardware RAID uses a dedicated RAID controller card (or a controller built into the motherboard) to handle all the striping, mirroring, and parity work.

• Frees up the main CPU

• Often faster and more stable for heavy workloads

• Easier drive swaps in many setups

• Usually more expensive

If you’re running serious web hosting, high-traffic applications, or big databases, hardware RAID on a dedicated server is often the safer long-term move.

And if you don’t want to fuss with controllers and tuning yourself, you can let a hosting provider handle it. Many providers ship dedicated servers with RAID preconfigured so you can just deploy and start using it.

RAID Levels At A Glance

There are many RAID levels out there, but in real-world server hosting you mostly see:

• RAID 0 – striping only, maximum speed, zero redundancy

• RAID 1 – mirroring only, high redundancy, simple and reliable

• RAID 5 – striping + single parity, balance of speed, capacity, and safety

• RAID 6 – striping + double parity, higher fault tolerance

• RAID 10 – mirroring + striping, high performance and high redundancy

Let’s walk through each level slowly and match them to real use cases.

RAID 0 – Maximum Speed, No Safety Net

RAID 0 splits data into blocks and stripes them across at least two disks. All drives work in parallel, so performance can be great.

What’s happening in RAID 0?

Imagine you’re saving a big video file. Instead of writing the whole thing to one drive, RAID 0 slices it into chunks:

• Chunk 1 goes to Disk A

• Chunk 2 goes to Disk B

• Chunk 3 goes to Disk A again

• And so on…

Reads and writes are fast because multiple disks work together.

Advantages of RAID 0

• Very fast read/write performance

• No parity or mirroring overhead

• Easy to set up and cheap in terms of capacity (you get all the space)

Disadvantages of RAID 0

• Zero redundancy

• If one disk fails, all data in the array is gone

• Not suitable for critical data, production databases, or serious hosting

Best use cases for RAID 0

• Video editing scratch disks

• Temporary processing workspaces

• Caching layers where data can be recreated easily

If you’d cry when that data disappears, RAID 0 is not for you.

RAID 1 – Simple Mirroring For Safety

RAID 1 keeps identical copies of your data on at least two disks. When you write data, it goes to both drives. When you read, it can read from either.

What’s happening in RAID 1?

Think of RAID 1 as a “spot the difference” game where both pictures are always the same:

• Data written to Disk A

• The same data written to Disk B

• If Disk A fails, the system keeps running from Disk B

Advantages of RAID 1

• High redundancy: one disk can fail and you keep working

• Simple to understand and manage

• Read performance can be as good as or better than a single disk

• Easy rebuilds: just copy data to the new drive

Disadvantages of RAID 1

• You lose half your raw capacity (two 1 TB disks give you 1 TB usable)

• Some setups require downtime to swap a failed disk

• Not as space-efficient as parity-based RAID (like RAID 5 or 6)

Best use cases for RAID 1

• Small business servers

• Accounting or finance systems

• Simple web hosting where data safety matters more than raw capacity

If you want something reliable but not overly complicated, RAID 1 is a solid starter RAID level.

RAID 5 – Balanced Performance, Capacity, And Protection

RAID 5 uses striping plus parity. You need at least three disks.

Data is spread across all drives, and parity information is also spread across them. If one drive fails, the array can reconstruct the missing data from the parity and remaining drives.

What’s happening in RAID 5?

• Data chunks go to different drives (striping)

• Parity chunks (math-based “check data”) go to rotating drives

• Lose one drive? The controller uses parity + remaining data to rebuild

Advantages of RAID 5

• Good read performance

• More efficient use of space than RAID 1 (you only “lose” the equivalent of one drive’s capacity for parity)

• Can survive one drive failure with no data loss

• Drives can often be hot-swapped with no downtime

Disadvantages of RAID 5

• Write performance is slower due to parity calculations

• Rebuild time after a drive failure can be long on large disks

• If a second drive fails during rebuild, data is lost

Best use cases for RAID 5

• File servers

• General-purpose storage

• Web hosting where you want decent performance and good capacity without going all-in on cost

For many medium-size hosting and storage needs, RAID 5 is a “good enough” middle ground—just be aware of rebuild time and disk size.

RAID 6 – Extra Safety For Bigger Arrays

RAID 6 is like RAID 5 but with double parity. You need at least four disks.

It can survive two drive failures at the same time, which starts to matter more as drives get bigger and arrays get larger.

What’s happening in RAID 6?

• Data is striped across all drives

• Two separate sets of parity data are stored across the array

• The controller can rebuild data even if two drives fail

Advantages of RAID 6

• Can handle two simultaneous drive failures

• Strong fault tolerance for large arrays

• Good read performance

• Hot-swappable drives mean no downtime for replacements

Disadvantages of RAID 6

• Slower writes than RAID 5 because of double parity calculations

• More overhead in usable capacity (you lose the equivalent of two disks to parity)

• Slightly more complex and CPU/Controller intensive

Best use cases for RAID 6

• Enterprise storage systems

• Database servers with large datasets

• Video archives and large media libraries

• Any environment where uptime and data availability are critical

If losing a storage array would ruin your week, RAID 6 starts to look very attractive.

RAID 10 – High Performance And High Redundancy

RAID 10 combines RAID 1 (mirroring) and RAID 0 (striping). You need at least four disks.

First, data is mirrored in pairs. Then those pairs are striped for performance.

What’s happening in RAID 10?

• Disk A mirrors Disk B

• Disk C mirrors Disk D

• Data is striped across the mirror pairs (AB and CD)

• You get fast reads/writes plus redundancy

Depending on which disks fail, RAID 10 can survive multiple drive failures, as long as both drives from the same mirror pair don’t die together.

Advantages of RAID 10

• Very fast reads and writes, great for I/O-intensive workloads

• Fast rebuilds because data is copied from the mirror, not recalculated from parity

• High redundancy and strong performance together

Disadvantages of RAID 10

• High overhead: half of the total raw capacity is used for mirroring

• More drives needed to reach large usable capacity

• Still vulnerable if both drives in the same mirror pair fail

Best use cases for RAID 10

• High-traffic databases

• Email and web servers with constant read/write activity

• Virtualization hosts and busy dedicated server hosting platforms

If you want both speed and safety and you’re okay with using more drives, RAID 10 is often the “premium” choice.

Choosing The Right RAID Level For Your Scenario

Instead of memorizing specs, think in terms of what you’re doing right now:

• I just need speed, data is disposable
  
  

  • Go with RAID 0 (scratch disks, temp data, cache)

• I want simple redundancy for important data, small setup
  
  

  • RAID 1 is usually enough

• I need a balance of capacity and protection for general file or web hosting
  
  

  • RAID 5 fits many mid-size storage needs

• I manage large arrays and uptime is critical
  
  

  • RAID 6 gives you more fault tolerance

• I run heavy databases or I/O-intensive apps and care about both speed and safety
  
  

  • RAID 10 is the go-to choice

As you scale, you’ll probably also care about where these disks live—inside a dedicated server, in a data center, under a managed hosting provider, and so on. Having a provider that knows RAID well saves you from learning every tiny controller option yourself.

If you prefer to get straight to spinning up a server that already has a RAID-optimized layout ready to go, you can use a hosting platform that focuses on fast deployment and dedicated servers. 👉 Explore GTHost RAID-ready dedicated servers and launch a configuration that fits your workload to skip the hardware guesswork and focus on your applications.

Conclusion

RAID 0, 1, 5, 6, and 10 each trade off speed, redundancy, and cost in different ways, and once you connect each RAID level to real server hosting scenarios—scratch disks, file servers, databases, high-traffic sites—the choice becomes much clearer. The main thing is knowing whether you care more right now about performance, capacity, or staying online when a drive dies.

If you want all this theory to turn into a working server without wrestling with controllers and arrays yourself, 👉 see why GTHost is suitable for RAID-optimized dedicated server scenarios where you need fast deployment and stable performance. That way you can let RAID do its job quietly in the background while you focus on running your services.