Question re: Using Raid 0 and 1 Together

[DavePlays]

Ok, so I have an idea and I'm not sure if it is crazy or not.

 

I currently have a single 3TB HDD in my system, and I want to expand my storage. Lets call this original drive HDD1.

 

My plan is buy 2 more 3TB drive (HDD 2 and HDD3).

 

And here's my plan:

Use software to create a RAID 0 between HDD2 and HDD3, then create a RAID 1 between HDD1 and the RAID 0.

 

 

Hopefully this diagram makes sense. I know that RAID 10 is probably a better move, but I can't afford a 4th hard drive.

 

Do you guys think this would work?

[Kakapipi]

3 minutes ago, DavePlays said:

Ok, so I have an idea and I'm not sure if it is crazy or not.

 

I currently have a single 3TB HDD in my system, and I want to expand my storage. Lets call this original drive HDD1.

 

My plan is buy 2 more 3TB drive (HDD 2 and HDD3).

 

And here's my plan:

Use software to create a RAID 0 between HDD2 and HDD3, then create a RAID 1 between HDD1 and the RAID 0.

 

 

Hopefully this diagram makes sense. I know that RAID 10 is probably a better move, but I can't afford a 4th hard drive.

 

Do you guys think this would work?

I wouldnt really recommend to put a hdd in raid 0, atleast if you dont care about losing data. Raid 0 is more a thing for ssd's 

[DavePlays]

Just now, Kakapipi said:

I wouldnt really recommend to put a hdd in raid 0, atleast if you dont care about losing data. Raid 0 is more a thing for ssd's 

Well the point of RAID 0 is for speed, so putting HDDs in RAID 0 is a common thing. The RAID 1 is meant to be redundancy for that RAID 0. 

[Kakapipi]

Just now, DavePlays said:

Well the point of RAID 0 is for speed, so putting HDDs in RAID 0 is a common thing. The RAID 1 is meant to be redundancy for that RAID 0. 

yes i know but putting HDDs in raid 0 isnt a smart idea in general 

[DavePlays]

@RandomGuy13I see your point. That does make sense...

[mikat]

the thing is though: you'd be limiting yourself to 1 drive worth of performance if hdd 1 is just as fast as 2 and 3

[NelizMastr]

This doesn't work. Combining RAID1 and 0 takes 4 drives minimum. It's called RAID1+0 or RAID10.  You can't mirror a 2TB RAID0 volume to a single 2TB drive for instance.

[trekkie1701c]

You can manually mirror HDD1 to the RAID 0 using something like clonezilla, but otherwise trying what you're trying would effectively be like putting two drives in a RAID 1.  Aside from the performance issues  everyone is talking about, the 3TB drive doesn't have enough space to use all the storage from the RAID 1, so you'd be limited to 3TB of space at a single drive's speed.  In other words, you could probably program the RAID software to do this, but you'd effectively be right back where you started, but out the money for two drives.

 

If you really want to do RAID with 3 drives, I think that's the minimum for RAID 5.  One drive will be reserved for Parity, though, so you'll just have two drives worth of storage.