JBOD / Raid 1 Suggestions

[Joey2Sites]

Hey guys, building my first pc since I was younger.  I never used RAID before but I think I have a decent grasp on it now.  I was thinking about running JBOD for my system including OS, and all programs on two Intel 730 240Gb SSDs.  And then run a RAID 1 on two 1Tb WD black drives which I could do nightly backups to.  

 

Questions:  

 

Thoughts?  

 

Can I add drives to a RAID later?  ie: could I just keep throwing additional WD 1Tb drives in the raid1 array later, or do they need to be wiped clean each time?  

 

Same with the SSDs..  I doubt I'd really need to add additional SSDs; I think 480Gb is enough since I'll have no videos, music, files, etc. on them aside from files I'm currently working on.  But this is just a question I don't see an answer for anywhere.

 

If I can't add drives to an array.. I guess I should forego the raid 1 for back ups.. and maybe wait until I can get a couple 2 or 3 Tb drives.

 

Thanks for any help

[ChineseChef]

Why use JBOD?  The purpose of JBOD is to use lots of mismatched drives (different sizes) to make 1 big logical disk, but there is no performance or security gain.  It basically just starts writing to one disk until its full and moves to the next disk.  JBOD enclosures can also be used to connect lots of disks to a system for use with software raid solutions, like Flexraid.

 

I think you are wanting RAID 0 with your SSDs, this combines them to create a single logical drive that is the combined size of the drives and increases performance.

 

Expanding arrays can be done relatively "easily".  The process is rather simple, but there are some pretty real risks of data loss/array failure.  One key thing here though, is your RAID controller must support this.  Expanding an array is a very time consuming and disk I/O intensive process.  Also, expanding a RAID1 array isn't as simple as you might hope, you would have to add drives in pairs, and you basically change the array from a RAID 1 to a RAID 10.

[Mighty_Miro_WD]

Hi there @Joey2Sites!

 

Once you setup your RAID 0 array with two drives, you cannot just break the stripe and add a HDD - you will loose all data if not backed up. In order to effectively add another drive to your RAID 0 implementation, you will have backup your machine, break the array, add the drive and then restore your image.

 

As for the RAID 1, no matter how many drives you add to RAID 1, the size never increases. What you increase is how many drives can fail and how good your read performance is. So 2x1TB drives in RAID 1 will be 1TB, and 10x1TB drives in RAID 1 will be 1TB - it never changes and the size is always the size of the smallest drive in the array. So if you plan to expand your array at some point, I think it will be better to go with RAID 5 (if you planning to have 3 drives) or RAID 6/RAID 10 (with 4 drives). 

 

However, I wouldn't recommend to go with more than 2 drives in the array since you're going to use WD Black because they're designed for stand-alone drives and consumer type RAID applications (RAID-0 / RAID-1 with two HDDs). They don't have the specific build-in features for RAID environment like WD Red for instance - RAFF, TLER, NASware 3.0 etc. You can take a look at this KB article for more information:

 

http://wdc.custhelp.com/app/answers/detail/a_id/996/related/1/session/L2F2LzIvdGltZS8xNDI2NDk4MzcyL3NpZC9sQzFpQXJobQ==

 

Hope this helps.

 

Cheers!

[Joey2Sites]

Well I was thinking Raid 0 but if one drive fails, both fail so I'm just a little worried about that.  With JBOD I thought it was just writing to them as they fill, and using the same drive letter.  

 

Why use JBOD?  The purpose of JBOD is to use lots of mismatched drives (different sizes) to make 1 big logical disk, but there is no performance or security gain.  It basically just starts writing to one disk until its full and moves to the next disk.  JBOD enclosures can also be used to connect lots of disks to a system for use with software raid solutions, like Flexraid.

 

I think you are wanting RAID 0 with your SSDs, this combines them to create a single logical drive that is the combined size of the drives and increases performance.

 

Expanding arrays can be done relatively "easily".  The process is rather simple, but there are some pretty real risks of data loss/array failure.  One key thing here though, is your RAID controller must support this.  Expanding an array is a very time consuming and disk I/O intensive process.  Also, expanding a RAID1 array isn't as simple as you might hope, you would have to add drives in pairs, and you basically change the array from a RAID 1 to a RAID 10.

 

[Joey2Sites]

Ok, thanks for the help.  I'll just start off with a non-raid setup.  I can always buy a couple drives later on and create a raid array for redundancy.  

 

 

Hi there @Joey2Sites!

 

Once you setup your RAID 0 array with two drives, you cannot just break the stripe and add a HDD - you will loose all data if not backed up. In order to effectively add another drive to your RAID 0 implementation, you will have backup your machine, break the array, add the drive and then restore your image.

 

As for the RAID 1, no matter how many drives you add to RAID 1, the size never increases. What you increase is how many drives can fail and how good your read performance is. So 2x1TB drives in RAID 1 will be 1TB, and 10x1TB drives in RAID 1 will be 1TB - it never changes and the size is always the size of the smallest drive in the array. So if you plan to expand your array at some point, I think it will be better to go with RAID 5 (if you planning to have 3 drives) or RAID 6/RAID 10 (with 4 drives). 

 

However, I wouldn't recommend to go with more than 2 drives in the array since you're going to use WD Black because they're designed for stand-alone drives and consumer type RAID applications (RAID-0 / RAID-1 with two HDDs). They don't have the specific build-in features for RAID environment like WD Red for instance - RAFF, TLER, NASware 3.0 etc. You can take a look at this KB article for more information:

 

http://wdc.custhelp.com/app/answers/detail/a_id/996/related/1/session/L2F2LzIvdGltZS8xNDI2NDk4MzcyL3NpZC9sQzFpQXJobQ==

 

Hope this helps.

 

Cheers!

 

 

[Joey2Sites]

My main concern is upgradability.  I'm just going to start with a single SSD for boot/applications and a 1tb hdd for file storage.

 

When I get close to filling the storage drive (and some time passes since I spent almost $2,000 on a new pc) I'll re-visit the raid idea.  Then I could just buy 4 WD red drives and run raid 5.  Or raid 1 if I get big enough drives.  I'm not going to buy a raid controller, and from what I hear Raid 5 parity is real slow on motherboard built in raid.    

 

Anyway, thanks for the advice.