Hardware Support Request

[smokey-chris]

Hi All

I want to build a TrueNas primarily for a PLEX server for media. I’ve picked a CPU for the processi9-10500K. 32GB ram and a 120GB SSD. A fractal case able to hold 10HDDs + 2SSDs

It is an upgrade to a QNAP 4bay (8TB) RAID5.

So from what I’ve been reading (forgive me I have spent hours reading and exhausted as I’m none the wiser). The setup for me is either z1 or z2(z2 I would prefer for the extra HDD failure).

Realistically i want to make it as future proof as possible. I have been looking at 3x 16TB WDpro drives (for now). I cannot afford more than 3hdds for now (at the least this is a good number to educate me on the next questions).

Questions I have:
(0) 3 HDDs for PLEX - the best option for redundancy here is z1 (e.g RAID5)

(1) If I want to add another 2x 16TB in the future to my 3x 16TB. My current understanding is this is not possible to increase the number of HDDs in the z1 zdev. A zdev once set can’t be amended easily.

(2) It is also not possible to add those 2 x 16TB hdd’s to the 3x 16TB hdd’s then convert the z1 vdev to z2 (e.g 3x storage and 2x redundancy). This 3new HDDs - I will have data on them and can’t really back it up to other drives to reconstruct the NAS.

(3) My current understanding is the best way of doing this would be to add another z1 vdev to the pool (the second zdev should also be 3hdd’s and use the same z1). The question part > If this is the case - If I had 2 hdd fails in the same zdev, the whole pool would be wrecked making data on the 3+1 working drives unusable. Is this correct. If this is the case, surely it would be safer to have 2 separate pools?

(4) I think I read somewhere that RAM in GB has to reflect the TB size.. Surely I have misunderstood thatI wouldn’t need 48GB of ram? It is that 48GB of storage space?

(5) To harden the system (I have a spare SSD) - I was thinking of backing up the main SSD for this. Either by duplicating all info of the SSD or using it for configuration files. I currently haven’t used TrueNas yet and am going to install today with the HDDs to get a better feel for it (well I have a few old 500GB/1TB desktop drives I may experiment with). Is this sensible, how do others backup the main OS?

Apologies for limited understanding, I feel it doesn’t matter how much I read now - that it will probably add confusion.

thanks
Chris

 

[ornias]

You are generally right.

However:
You might be better of with 10 cheaper and smaller harddisks, and replace those as-you-go with 16TB harddrives. As soon as all are replaced, you can use the complete capacity of the new drives :)

About the ram:
It's a general guideline, generally speaking 32GB is more than good enough for a home-media-server

 

[Etorix]

(0) The best option for redundancy with 3 drives is actually a 3-way mirror. Yes, that's terrible for storage, but raidz1 with large HDDs is not really safe.
(1) A raidz# vdev cannot be modified afterwards, full stop. You can replace drives, and replacing all drives with larger ones will eventually increase capacity.
(2) Changing Z1 into Z2 is in the works, but if and when it is eventually released it will come with a big nasty caveat anyway (old data will keep the old level of redundancy).
(3) Correct. 2 failed drives = dead raidz1. Any dead data or special vdev = lost pool.
(4) It's a rule of thumb, not a hard rule.
(5) For a home NAS, just keep a copy of the configuration file outside of the NAS and don't bother mirroring the boot drive. If the boot drive fails, buy another one, install the same version of TrueNAS on the new drive and upload the configuration file.

Z1 is not really advisable, and certainly not as one single 10-wide vdev.
A 10-wide Z2 is possible, but two 5-wide Z2 would be safer. You can begin with one and add the second later, either as a second pool or in the same pool, but that involves bringing in five drives at a time.