Understanding the future of my hardware if I choose to use FreeNAS

[Shannon Mason]

So I understand that once I setup a zpool with a vDev I cannot remove a vDev ever? (even if I create a 2nd vDev?) I do realize that I can upgrade the hard drives one by one but since creating a 2nd vDev in the same zpool would naturally make it impossible to remove the vDevs as they work together. Is it possible to create a new zpool with new vDevs and then unmount the old vDev and old zpool? OR am I better off building a new system with even MORE HDDs than the last one when I outgrow my 1st one?

I also understand that mirroring does not let you utilize more space, so what are my options if I don't want to mirror? If I don't mirror then I don't have any data redundancy?

My current configuration is going to be 1 USB flash drive to hold the OS (8GB) 4x4TB SATA HDDs running on an AMD FM1 2.5GHz CPU with 16GB RAM 2x8GB (I have room for 2 more HDDs but I don't have the case space for it. And I am new to this but I have a basic understanding of mirroring, raid0/1 and how raidz1 and raidz2 are similar and the advantages of ZFS vs hardware raid so not to worry there :).

 

[Stephens]

Build the NAS you want now if at all possible. It isn't worth the headache trying to piecemeal it. Anything you do to add vdevs later to expand storage will not end up the same as if you built it complete to begin with.

Cases are relatively cheap. Don't fit your NAS to your case, fit your case to your NAS. If your motherboard support 6 drives, get a case that does as well.

You don't say how you plan to arrange your 4x4TB drives. Hopefully you're aware of the general trend that larger drives fail more often. 4x4TB RAIDZ1 isn't an optimal configuration. 5x4TB RAIDZ1 is optimal, as is 6x4TB RAIDZ2 (they give 16TB usable). If you don't see ever needing that much space, you can use much cheaper 3TB drives (which is what I'm doing on my latest build). Keep in mind I only see ~7.2TB on a fresh install of a 6x2TB NAS. Additionally, you don't want your NAS to fill up as it'll be less stable.

 

[Brosif_My_Nif]

Build the NAS you want now if at all possible. It isn't worth the headache trying to piecemeal it. Anything you do to add vdevs later to expand storage will not end up the same as if you built it complete to begin with.

Cases are relatively cheap. Don't fit your NAS to your case, fit your case to your NAS. If your motherboard support 6 drives, get a case that does as well.

You don't say how you plan to arrange your 4x4TB drives. Hopefully you're aware of the general trend that larger drives fail more often. 4x4TB RAIDZ1 isn't an optimal configuration. 5x4TB RAIDZ1 is optimal, as is 6x4TB RAIDZ2 (they give 16TB usable). If you don't see ever needing that much space, you can use much cheaper 3TB drives (which is what I'm doing on my latest build). Keep in mind I only see ~7.2TB on a fresh install of a 6x2TB NAS. Additionally, you don't want your NAS to fill up as it'll be less stable.

Stephens, could you elaborate on your last sentence? "Additionally, you don't want your NAS to fill up as it'll be less stable." At what percentage of reaching full capacity will FreeNAS become less stable?

 

[Shannon Mason]

When I got the hardware I was going to use WHS and was going to do JBOD but everybody kept saying I should just do FreeNAS and I want to try FreeNAS but at this point it makes no sense to buy 2 more 4TB drives its already built and I'll upgrade later when I know how much more usability I'll need/get out of it.

I know that RAIDZ1 is not optimal; so I guess neither is RAIDZ2

 

[cyberjock]

When I got the hardware I was going to use WHS and was going to do JBOD but everybody kept saying I should just do FreeNAS and I want to try FreeNAS but at this point it makes no sense to buy 2 more 4TB drives its already built and I'll upgrade later when I know how much more usability I'll need/get out of it.

I know that RAIDZ1 is not optimal; so I guess neither is RAIDZ2

Elaborate on who "everyone" is that keeps saying you should do FreeNAS?

Why is RAIDZ1 not optimal? And why is RAIDZ2 not optimal either? What do you mean not "optimal"? Because you lose storage space compared to a JBOD? You do understand that a JBOD provides no data protection from a loss of a hard drive. In your case you'd lose ALOT of data if 1 disk fails.

 

[paleoN]

Why is RAIDZ1 not optimal? And why is RAIDZ2 not optimal either?

Actually, raidz1 isn't optimal as they are using 4TB drives. I wouldn't run 4TB drives in a single-parity array. I wouldn't be comfortable even mirroring them.

The 4 x drive raidz2 configuration is an aligned one. A 6 x disk raidz2 is probably the "optimal" one as it's also aligned and you lose 1/3 of the drives to parity vs half the drives.

 

[cyberjock]

I understand that, but the poster made the post sound like "I need as much data space as possible and parity will cost me too much space". Especially since she took 4TB drives and set them up as a JBOD when WHS(last time I checked years ago) does support software RAID5.

It just really caught me off guard with no protection for 16TB of storage space.

 

[Stephens]

Stephens, could you elaborate on your last sentence? "Additionally, you don't want your NAS to fill up as it'll be less stable." At what percentage of reaching full capacity will FreeNAS become less stable?

For instance...
ZFS Best Practices

Keep pool space under 80% utilization to maintain pool performance. Currently, pool performance can degrade when a pool is very full and file systems are updated frequently, such as on a busy mail server. Full pools might cause a performance penalty, but no other issues. If the primary workload is immutable files (write once, never remove), then you can keep a pool in the 95-96% utilization range. Keep in mind that even with mostly static content in the 95-96% range, write, read, and resilvering performance might suffer.

 

[Brosif_My_Nif]

For instance...
ZFS Best Practices

Thank you for the addition information. I was always wondering if and when filling up my pool would begin to degrade performance. I am nearing 80% capacity and just purchased x6 more 3TB disks. I'll get those new drives in sooner rather than later.

 

[Shannon Mason]

I've already setup my FreeNAS and its working fairly nicely although I am still learning; some things are easier to configure and figure out than others.

I thought I had 4x4TB but its actually 4x3TB dunno why I thought I had 4TB drives After copying a lot of data lately from almost every PC (I've still got more to do) I'm barely scratching 1% but I still have tons more data to obtain from various drives I've been saving to recover files from (the drives are still in good working order, just those machines were/are no longer viable). by the time I am completely setup I should have close to 200GB worth of data sadly... I thought I'd come closer to 300-400GB and this doesn't include data from two of my mom's hard drives so I'm still working on that.

I'm setup with RAIDZ2 4x3TB which gave me 5.2TB worth of storage I'm happy with that performance seems to vary, so for what I'm using it for right now seems to be decent; I'll let you know in 2-3 months.