Need Help Configuring NAS/DAS Build

[Krrey]

Hey guys, currently looking to put together a NAS/DAS, will mostly be used as a DAS currently: as I don't have 10 GB Ethernet. And after watching dozens of hours of videos and reading a few articles. I still need a few things cleared up before moving forward. Thanks in advance


1. Objective
• 300+ MB/s read & write performance
• I would love to be able to edit footage from it, But I would be okay if I couldn't, as I currently have about 6TBs of SSDs in my computer that I can just use for active project folders
• I currently shoot 4K Black Magic RAW
• I'll be connecting to it via USB 3.1 for the time being
• NAS features such as remote access, and file sharing, are not extremely important to me, So if there are significant cost savings involved, I would like to forego any and all parts that are strictly for NAS purposes.
• Ideally, I would like to start with 4 drives ( 6-8) TBs, most likely set up in a Raid-10 array

2. Things I mainly need clarified
• Given how useful NAS features can be, should I spend the extra money to keep it a NAS/DAS?
• Given the fact that I'll be using USB 3.1 & and 7,200 RPM drives, what can I expect my READ & WRITE speeds to be when reading the HDDs?
• if my ultimate priority is performance, and future of good ability. Should I use Free NAS or unRAID? From what I hear, free NAS might be the better option, but because it uses ZFS I can't easily add more storage to my already existing system?
• if possible I would like to add hardware to accelerate my raid. But it seems like raid cards don't play well with software raid . I would love to know if there's a potential workaround around to this, because once again reading writes reads are my priority.

Thank you for your help!

 

[jgreco]

Welcome to the forums. This appears to be a hot mess, so I'm mainly going to just make unapologetic corrections, to avoid wasting your time and my time, and try to get you up to speed quickly. This is a bit of throwing you into the deep end. Sorry. :-/

will mostly be used as a DAS currently:

Then you're in the wrong place. FreeNAS/TrueNAS do not have the ability to function as DAS.

300+ MB/s read & write performance

That's not how hard drives work. Hard drive performance is based on the number of seeks, so if you have I/O that requires lots of seeks, you may not be able to achieve an arbitrary speed goal. If we mean MBytes/sec, I'll note that four contemporary HDD's arranged as two mirror vdevs can achieve these speeds as long as the traffic to the drives is sequential. However, if you had lots of small file traffic, you might need dozens or hundreds of drives and a massive amount of ARC/L2ARC to get there.

I'll be connecting to it via USB 3.1 for the time being

Well, no, you won't, at least not with FreeNAS/TrueNAS/unRAID, which are NAS products, and require you to access them over IP networking of some sort. You might be able to get a USB-to-ethernet adapter that's 10G or IP-over-thunderbolt, but it will still be network-based.

set up in a Raid-10 array

ZFS doesn't do conventional RAID levels or arrays. Some people say things like RAID10 meaning "two mirror vdevs" which is a similar ZFS construct; ZFS doesn't create arrays, but rather pools. Using incorrect terminology is confusing to community participants, and we ask that people use the correct terminology. Please review

Terminology and Abbreviations Primer

We realize that new users have a lot to learn when they come to FreeNAS. There's a certain amount of confusion added to discussions when users pick random/approximate terms to describe things. I've spent a lot of time quietly trying to translate terms on the reader's side when reading posts...

www.truenas.com

should I spend the extra money to keep it a NAS/DAS?

I don't even know what you'd spend money on to accomplish that. I'm all ears though!

7,200 RPM drives, what can I expect my READ & WRITE speeds to be when reading the HDDs?

7200 RPM drives often don't give you much of a speed advantage with ZFS, which tends to have peculiar behaviours due to the way it lays down files, and how the CoW properties of ZFS interact with performance enhancing features like the ARC/L2ARC. You can really get SSD-like speeds out of a HDD array if you keep the occupancy rates low, have lots of ARC/L2ARC, and have cacheable traffic patterns. Write speeds are more nearly just a function of the number of drives and pool occupancy rates; a pool that is only 10-25% full will typically be allocating space contiguously even for random writes, and will thus write at speeds directly tied to the speeds of the underlying HDD's.

free NAS might be the better option, but because it uses ZFS I can't easily add more storage to my already existing system?

ZFS isn't like a DROBO or unRAID where you can just add another disk. However, you can easily replace your existing disks with larger ones, or add additional vdevs to an existing pool. There are a bunch of good ZFS primers out there.

hardware to accelerate my raid.

Yes. RAM. Add lots of RAM. This is the biggest ZFS accelerator. (I know that's not what you were thinking).

But it seems like raid cards don't play well with software raid . I would love to know if there's a potential workaround around to this, because once again reading writes reads are my priority.

RAID cards aren't a good choice, and they generally make systems perform WORSE. In the ZFS design, ZFS itself IS your RAID controller, and it is both MUCH more performant and MUCH more capable than your typical hardware RAID card.

What's all the noise about HBAs, and why can't I use a RAID controller?

1) An HBA is a Host Bus Adapter. This is a controller that allows SAS and SATA devices to be attached to, and communicate directly with, a server. RAID controllers typically aggregate several disks into a Virtual Disk abstraction of some sort...

www.truenas.com

A modern high-end RAID card such as a Dell PERC H740P has an 8GB onboard cache and can handle up to 32 drives. A ZFS system can easily be built with 256GB or more of system RAM (most of which gets used as ARC), and can handle hundreds or even a thousand drives. The crappy little CPU in an H740P is a dual-core ARM A15, around 4200 Dhrystone MIPS, while a ZFS based system can be outfitted with crazy massive amounts of Xeon CPU.

People who are used to seeing something like the H740P provide great levels of acceleration to a Windows Server or ESXi host aren't wrong that it's a good controller in those roles, but ZFS has massive potential to totally swamp it. A ZFS transaction group on a 256GB filer with a hundred drives might be many gigabytes; sending that kind of data out to a ZFS pool every five seconds is going to be a mess.