"Software RAID" ?

bigflyer · Wed Apr 29, 2015 10:58 am

I've seen that the 'requirements' for Virtual SAN say "Please note that the use of software based RAID arrays in the Virtual Virtual SAN environment is not supported.". What does this mean? Does it mean the cheap Fake-RAID controllers on some motherboards, or does it mean Windows 'RAID' (or both)?

The reason I ask is that, planning ahead, I wonder what will happen if we need to increase the size of a HA device.

The servers have P420is in them, so they are real-RAID controllers, but I can only expand an existing RAID 10 array by using drives of the same size. If I could use different drives and use the Windows 'spanned volumes' (or 'extend volume'), then it wouldn't be as restrictive.

Is it allowed/safe/supported to use the Windows 'extend volume' facility?

thefinkster · Thu Apr 30, 2015 2:11 pm

I would bet money "Software RAID" includes the Dynamic disks from windows. Software RAID controllers (S110 from Dell for example) also would count. Both of those are considered "software RAID".

Fri May 01, 2015 11:10 am

Honestly speaking it does change once in a while... So "fake RAIDs" are still not OK (either use OS built-in logical volume manager features or go for hardware RAID) but say Storage Spaces with some efforts from our side are definitely production ready now. I'll check do we need to review and flex out this requirement or re-phrase it at least. Thanks for pointing

P.S. Hardware RAID controller with NVRAM cache like Dell PERC 8xx is still recommended.

bigflyer · Fri May 01, 2015 1:07 pm

anton (staff) wrote:(either use OS built-in logical volume manager features or go for hardware RAID)

Does this mean Windows 'Dynamic Disks' are OK, with their spanning/mirroring facilities?

We have HP P420i hardware RAID, but they're quite limiting when it comes to expanding volumes. Using dynamic disks on top of the hardware RAID 10 would give us extra flexibility when expanding volumes.

Or should we skip dynamic disks and use storage spaces instead?

Fri May 01, 2015 2:50 pm

Dynamic disks are deprecated by Microsoft and Storage Spaces are (is?) successor. So you CAN use Storage Spaces in production (just make sure you don't create 512e bytes sector volumes on top of 4KB Storage Spaces) but don't expect performance being too high

bigflyer wrote:
anton (staff) wrote:(either use OS built-in logical volume manager features or go for hardware RAID)
Does this mean Windows 'Dynamic Disks' are OK, with their spanning/mirroring facilities?

We have HP P420i hardware RAID, but they're quite limiting when it comes to expanding volumes. Using dynamic disks on top of the hardware RAID 10 would give us extra flexibility when expanding volumes.

Or should we skip dynamic disks and use storage spaces instead?