(old title: Storage Spaces on stand-alone Windows Server 2019 Datacenter: what are my options with 2x SSD and 4x HDD?)
I have 2x 1.75TB SSD + 4x 3.64TB HDD. I thought to use Storage Tier but I am unable to create a Virtual Disk for my Data Storage Pool.
I've been playing around for some time now (https://docs.microsoft.com/en-us/answers/questions/275652/2x-175tb-ssd-4x-4tb-hdd-but-creating-a-volume-give.html?childToView=277348#answer-277348 – The storage pool does not have sufficient eligible resources for the creation of the specified virtual disk) and I'm unable to get anything created*
So clearly I'm overlooking something very obvious. Therefore my question for the ppl with hand-on experience: what should I be able to do with these 6 disks (when needed, I can add a 5th 3.64TB HDD)?
I like the idea of Storage Tiers (hot data on SSDs, cold data moved to HDDs) and I really need to be able to survive 1 or even 2 disk crashes without losing any data.
What's wisdom here pretty please? 🙂 Am I fighting with a bug or with my own lack of knowledge?
Appreciated!
*2 exceptions, but I don't know wtf I ended up with; nor did the numbers make any sense to me.
https://docs.microsoft.com/answers/comments/275805/view.html
POST-EDIT 01: I can add a 5th HDD right now (but I'd prefer not to) and in total I could have 8 bays in use (though I'd like to reserve 1 bay for a big ass HDD)
POST-EDIT 02: while the step-by-step seems to fail, I did get it working. But the results are weird to me.
These are the commands I am testing with ("OpslagBad is the Storage Pool I created with the GUI):
New-StorageTier -StoragePoolFriendlyName OpslagBad -FriendlyName performance -MediaType SSD
New-StorageTier -StoragePoolFriendlyName OpslagBad -ResiliencySettingName Parity -FriendlyName capacity -MediaType HDD
New-Volume -FriendlyName 2SSD4HDD -FileSystem ReFS -StoragePoolFriendlyName OpslagBad -StorageTierFriendlyNames performance, capacity -StorageTierSizes 1.7TB, 3.6TB
My disks are 1.75TB and 3.64TB but if I enter those sizes, New-Volume fails.
Now for the experimenting part 🙁
1x SSD + 1x HDD fail for New-Volume. As it does for 1x SSD + 2x HDD and 2x SSD + 2x HDD. I'm willing to accept that without knowing why 🙂
With 2x SSD and 3x HDD I do end up with a volume. Its size is 5.30TB. With 3x 3.6TB + 2x 1.7TB (= 10.8TB + 3.4TB = 14.2TB of disks). That's a big hit but could make sense – the fewer the amount of disks, the worse the impact of parity. I should be happy now. But I have more disks, so let's go on and increase efficiency.
So I add a 4th HDD to the Storage Pool and repeat the PS commands (after removing the current virtual disk). I AGAIN end up with a 5.3 TB virtual disk… wtf? what happened to all that extra disk space? What is Windows doing here? Can I control this somehow? Storage efficiency should go up, not get less, with more disks!
So I try with a 5th HDD disk added (so 2x SSD + 5x HDD). AGAIN I only have a 5.3TB virtual disk (5.25TB free). What happened to those 2x HDDs I added?? Why isn't my storage space increasing? 🙁
Best Answer
I’d suggest you to stick with so-called mirror accelerated parity. It’s not supported officially for non-OEMs, but it works just fine for many scenarios. You’ll get best disk usage with it and you’ll able to survive double disk faults. Here’s a good guide on that.
http://knowledgebase.45drives.com/kb/kb450193-creating-mirror-accelerated-parity-volumes-and-storage-tiers-in-storage-spaces-windows-server-2019/