So I was reading that the Pro version only supports upto 30 storage devices. Is there another tier not listed? How are others using unraid with 45+ drives?

30 in the parity protected array. The cache pool can hold 24 more.

So if I want more than 28 drives (+ 2 parity drives) that are protected, I would need to build another server and get another copy of unraid? Is this a limitation due to the software/hardware, or a limitation they implemented? How are people using 45+ drives saying its all part of an array, not a cache pool. I have even seen youtube video where people have them storminator 45 drive case all filled for storage.

 

Just trying to get clarification. (Also since storminator pushes unraid for their servers)

The cache pool can run any valid BTRFS RAID level so it is protected as well. Some BTRFS RAID configurations are more stable than others, due to limitations with BTRFS, not specific to unraid.

The cache pool is somewhat misnamed, as it is a holdover from early iterations of unraid. It would be more accurate to call it an application or VM pool, the caching function is seldom used when filling out a full complement of drives. It's more of a higher speed single volume space vs. the parity protected slower individually accessible array drives.

Tier explanation can be found here https://unraid.net/pricing

Ok so still a bit confused. I have read the tier stuff, and i get the cache pool. But still curious how people are using more than 30 drives in unraid. Example: Linus from linus tech tips. 1 petabyte of storage and using unraid. (about 100 drives?) so how it that possible if were limited to 30 + 24. Just thinking ahead for future storage needs. (I remember when 1GB drives came out for over $400+ and I got one thinking it would last me forever and it was filled within a year.)

Pro = Unlimited attached storage devices.

32 minutes ago, BRiT said:

Pro = Unlimited attached storage devices.

Thats what I thought as thats what it says, but then you read the section under Registration Key Info and is says:

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*Attached storage devices refers to the total number of storage devices you are allowed to have attached to the server before Starting the array, not counting the USB Flash boot device. There are no other limitations in the software based on registration key type.

 

* Unraid OS Pro supports up to 30 storage devices in the parity-protected array (28 data and 2 parity) and up to 24 storage devices in the cache pool. Additional storage devices can still be utilized directly with other Unraid features such as Virtual Machines or the unassigned devices plugin.

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This is why I am confused

1 minute ago, almulder said:

Unraid OS Pro supports up to 30 storage devices in the parity-protected array (28 data and 2 parity) and up to 24 storage devices in the cache pool. Additional storage devices can still be utilized directly with other Unraid features such as Virtual Machines or the unassigned devices plugin.

Not sure why that's confusing. Unraid only directly manages the parity protected array and the cache pool. You can use any number of additional drives as individual or manually pooled devices, they just won't participate in user shares. You can still manually share them, write to them, whatever.

On 10/4/2019 at 7:59 PM, almulder said:

Is this a limitation due to the software/hardware, or a limitation they implemented?

I would also be interested in knowing the reasons for the limitation.

IIRC current super.dat format where the disk assignments are stored can't support more than 30 devices, doesn't mean it couldn't be changed but likely not without a lot of work.

Supporting more than 28 data drives with just 2 parity drives is questionable from a sensibility standpoint. To genuinely protect more than 28 data drives one should really have multiple array pools, each with their own set of parity drives. This requires substantial development efforts from where things stand today.

22 hours ago, BRiT said:

Supporting more than 28 data drives with just 2 parity drives is questionable from a sensibility standpoint. To genuinely protect more than 28 data drives one should really have multiple array pools, each with their own set of parity drives. This requires substantial development efforts from where things stand today.

That's kinda what I was thinking, I was hopping someone was going to day per array, but I guess we can really only have one protected array for now and the foreseeable future. I guess worst case when I run out of space and want more I would just have to build another server and get another licence. 

12 minutes ago, almulder said:

I guess worst case when I run out of space and want more I would just have to build another server and get another licence. 

If you have another license then in is possible to run a second instance of Unraid in a VM and pass the additional drives to it.  That is how I actually run an Unraid test environment on my main Unraid server.   Whether that would be better than having a second server depends on whether you want to save money and are not too demanding on what you want from the second Unraid instance.