[SOLVED] Addressing fast storage in pool?

[David Dernovoj]

I just set up my Unraid earlier (thanks to the help from the forum, had UEFI boot issues) and started messing around with it.

 

I have a huge (logical) HDD from my RAID controller (that runs RAID 6), and 4x 4 TB NVMe SSDs. My initial instinct was to use the huge (logical) HDD as the storage pool, and the 4 NVMe SSDs as a Cache. However, is there any way to specifically address the SSDs as actual storage, to have them work fast all the time? Or am I just not getting the mentality of this storage approach that I need to rethink?

 

Here's my storage array configuration right now. I have still not set up anything of value, so I can reformat and throw over everything without any hassle.

 

Edited July 4, 2020 by David Dernovoj

[JorgeB]

14 hours ago, David Dernovoj said:

I have a huge (logical) HDD from my RAID controller (that runs RAID 6),

This isn't a really recommended way of using Unraid, you can do it, but at least make sure you have a way of monitoring the RAID and individual disks health, i.e. make sure you're warned if there's a problem with the RAID or it might be too late when you notice.

 

14 hours ago, David Dernovoj said:

is there any way to specifically address the SSDs as actual storage,

The cache pool can be used as direct storage, it just dependents on how you configure the use cache setting for your shares, also with 4 devices I would use btrfs RAID10 (or RAID5 if you have good backups).

[David Dernovoj]

7 hours ago, johnnie.black said:

This isn't a really recommended way of using Unraid, you can do it, but at least make sure you have a way of monitoring the RAID and individual disks health, i.e. make sure you're warned if there's a problem with the RAID or it might be too late when you notice.

 

The cache pool can be used as direct storage, it just dependents on how you configure the use cache setting for your shares, also with 4 devices I would use btrfs RAID10 (or RAID5 if you have good backups).

So is there any specific way I should be setting this up? I don't really want to toss the raid controller.

 

How or where exactlly should I be setting up the cache? I don't really see a lot to configure in the storage array. Sorry if I'm being a pain and need to RTFM, please just point me where I should read up if that's the case and I'll go ahead and do that. I've tried looking into the documentation, but haven't quite found what I'm looking for so far.

 

Edit: are we talking about this?

 

Edited July 4, 2020 by David Dernovoj

[trurl]

Here is the wiki Overview:

https://wiki.unraid.net/UnRAID_6/Overview

 

Not sure there is much point to cache when your are bypassing all the "Unraid stuff" with RAID6.

 

[trurl]

24 minutes ago, trurl said:

Not sure there is much point to cache when your are bypassing all the "Unraid stuff" with RAID6

I guess you could just use cache as a separate storage pool by making some cache-only user shares for it.

[trurl]

41 minutes ago, David Dernovoj said:

Edit: are we talking about this?

yes

[David Dernovoj]

1 hour ago, trurl said:

yes

Okay, thanks.

 

I have one last question: why is it that my cache is only 50% of my 4 SSDs? Is it doing some mirroring between them, effectively being something comparable to a RAID10?

[itimpi]

The default,configuration for the cache is BTRFS version of raid1

[David Dernovoj]

3 minutes ago, itimpi said:

The default,configuration for the cache is BTRFS version of raid1

Ah alright that explains it... I guess I shouldn't have just pressed add and run 

[itimpi]

You can change the configuration dynamically with btrfs by clicking on the cache entry on the Main tab.

[trurl]

 

[David Dernovoj]

Thanks itimpi and trurl, that helps a lot.

I marked the topic as solved by editing the title, I hope that's correct.