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Building a Budget Homelab NAS Server

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21–30 of 316 posts

Re: Building a Budget Homelab NAS Server

#21
post #13

How do you handle backups of such amount of data?

A 22TB pool can perhaps be backed up to a single 26TB drive (over USB? Thunderbolt?):

* https://www.techradar.com/news/larger-than-30tb-hard-drives-...

Buy multiple drives and a docking station and you can rotate them:

* https://www.startech.com/en-us/hdd/docking

ZFS send/recv allows for easy snapshotting and replication, even to the cloud:

* https://www.rsync.net/products/zfs.html

* https://arstechnica.com/information-technology/2015/12/rsync...

Re: Building a Budget Homelab NAS Server

#22
Thanks for including energy usage in the article. I carry USB-C SSDs around the house for backups and storage of archived files. Of course this is a bit of a hassle and I played with the idea of either buying or building a NAS. My current standby consumption for all computer stuff (access points, router, switches, a dozen or so microcontrollers and various SmartHome stuff, but not TVs, running computers or gaming consoles) is already above 100w and I would really like to bring this number down. An extra 30-60w makes it really hard to justify the purchase of a NAS ( that I don’t really need). I thought at least the synonogies would use way less power when not in use, so thanks for making me aware of this.

Re: Building a Budget Homelab NAS Server

#23
I think using 1 disk redundancy is a mistake. It’s not only physical failure you’re worried about, it’s an error upon rebuild when you lose a drive. Bit rot on your remaining drives can occur which wouldn’t be detected until rebuild time when you lose a drive, and that could cause you to lose your entire volume. Bit rot can be checked for but you can’t always be sure and with larger and larger sets of data it gets slower to do.

I use raid 6 and also backup my data externally to another nas as well as backup to a static usb drive. Backup requires multiple different types since failures are so catastrophic and can occur in ways you don’t expect.

Re: Building a Budget Homelab NAS Server

#24

Why is there a need to proselytize about ZFS in every thread on this topic?

Because people don't know about cephfs yet, and the silliness of degraded raid setups. i.e. trusting a zfs community edition in a production environment can be a painful lesson. ;-)

Re: Building a Budget Homelab NAS Server

#26
post #10

Nice article - though one misstatement is that ZFS dies not allow you add disks to a pool. It does [1] [2], by adding new vdevs. The linked issue is about adding support for expanding existing vdevs instead. [1]: https://openzfs.github.io/openzfs-docs/man/8/zpool-add.8.htm... [2]: https://docs.oracle.com/cd/E53394_01/html/E54801/gayrd.html

It's a hard pill to swallow, adding two more drives in a vdev to get one more drive worth of storage (authors case maxes out at 6 drives, currently has 4). So often you will bite the bullet and just completely rebuild.

True RAIDz expansion is something that's supposed to be coming, possibly in Q3 2022, so it may be that by the time one needs to expand a volume, that ability will have landed. That'll be a game changer.

Re: Building a Budget Homelab NAS Server

#27
post #7

I wish there was a good guide for buying JBOD hba cards. I want to replace my drobo with all SATs ssds.

Get LSI 2000 or 3000 series SATA cards. Several manufacturers make them approximately to the reference spec. The drivers are in the Linux kernel. If they don't come flashed to the IT spec firmware (no RAID capabilities), do that, but the cheap ones usually do. The 4i models sometimes come with ordinary individual SATA connectors; the 8i will have one of two kinds of combo connectors that can accept cables that go to a backplace or breakout cables to ordinary SATA connectors.

There you go.

Re: Building a Budget Homelab NAS Server

#28
> I chose raidz1. With only a handful of disks, the odds of two drives failing simultaneously is fairly low.

Only if you buy different hard drives or at least from different production batches. I had a lot of trouble on the same premise and I won't make that mistake again.

Edit: He mentioned it though ( a bit later in the article)

> The problem is that disks aren’t statistically independent. If one disk fails, its neighbor has a substantially higher risk of dying. This is especially true if the disks are the same model, from the same manufacturing batch, and processed the same workloads. Given this, I did what I could to reduce the risk of concurrent disk failures.

> I chose two different models of disk from two different manufacturers. To reduce the chances of getting disks from the same manufacturing batch, I bought them from different vendors. I can’t say how much this matters, but it didn’t increase costs significantly, so why not?

Re: Building a Budget Homelab NAS Server

#29
I've gone the TrueNAS route, but I'm running it on a QNAP TS-451. I'm running TrueNAS off of a USB stick hanging off the back, so I didn't have do to anything with the hardware and reverting back to QTS is just a matter of setting the boot order in the BIOS.

I really like seeing other people's builds, but I know that building my own computer isn't something I want to do. I was happy to see the comparison between the DIY model and the roughly-equivalent commercial units. I'll likely buy another QNAP (to run TrueNAS on) when the time comes, and the comparison tells me that I won't get screwed too badly by doing so.

Re: Building a Budget Homelab NAS Server

#30
I don't know Im no longer feel save with >4tb drives and raidz1.

I run two offline Nas (I unpower them and do scrabing every month) and have one with raidz2 for all critical things like my photos.

To resilver 8tb takes ages and while he wrote his thoughts on it, I was missing the repair risk calculation

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