Another vote for TrueNAS. I’ve been running FreeNAS (the old name of the free community version) and TrueNAS Core for over seven years without any issues or data loss. I currently have two servers: one old rack mounted DIY build and another TrueNAS Mini appliance from iXsystems.
Bear in mind that ZFS, with all its great features, is intolerant to crashes, and there is a near-zero chance of recovering a corrupt ZFS pool. So make sure you back up your unique data to another device or into the cloud. If you build your own NAS, pay close attention to hardware recommendations and best practices, such as ECC RAM, UPS.
Another vote for TrueNAS. I’ve been running FreeNAS (the old name of the free community version) and TrueNAS Core for over seven years without any issues or data loss. I currently have two servers: one old rack mounted DIY build and another TrueNAS Mini appliance from iXsystems.
Bear in mind that ZFS, with all its great features, is intolerant to crashes, and there is a near-zero chance of recovering a corrupt ZFS pool. So make sure you back up your unique data to another device or into the cloud. If you build your own NAS, pay close attention to hardware recommendations and best practices, such as ECC RAM, UPS.
Eh, I wouldn't bother with ECC RAM personally. It offers very little benefit. Even as a user who has a server rack and enterprise gear at home, if I was to rebuild my NAS, I wouldn't bother with ECC RAM. It really doesn't matter.
As for "intolerant to crashes", I strongly disagree. I've had servers simply switch off after the UPS battery dies, with no impact to the ZFS pool. ZFS is extremely resiliant. Even in cases of the underlying OS crashing, ZFS should remain intact. Severe file system damage (ZFS or otherwise) is usually either the sign of hardware problems, or user error (or both). For example, allowing the pool to degrade to such a point that you're forced to try and restore data from a failing hard disk in order to restore your pool.
ZFS is an extremely robust and resiliant file system. Would highly recommend it, but regardless, always have a backup of your data on seperate media. I still don't consider ZFS as a form of "backup", just like traditional RAID isn't.
If the NAS crashes before it syncs pending metadata changes to disks (where metadata stands for file allocation tables of the beautiful COW file system), your entire ZFS pool will be lost with little prospect of recovery. And unlike inferior NTFS, FAT32, and EXT file systems, you will not find any tool, commercial or open source, to salvage even a fraction of data from a bad ZFS pool.
If the NAS crashes before it syncs pending metadata changes to disks (where metadata stands for file allocation tables of the beautiful COW file system), your entire ZFS pool will be lost with little prospect of recovery. And unlike inferior NTFS, FAT32, and EXT file systems, you will not find any tool, commercial or open source, to salvage even a fraction of data from a bad ZFS pool.
That's the entire point of copy-on-write file systems, like ZFS. It's designed to withstand sudden power failures or incomplete writes, without catastrophic loss of data. Live, good data is never overwritten and that includes the metadata.
I'd keep power consumption in mind. A pc in any form isn't particularly efficient.
I'd keep power consumption in mind. A pc in any form isn't particularly efficient.
I'd keep power consumption in mind. A pc in any form isn't particularly efficient.
Bear in mind that ZFS, with all its great features, is intolerant to crashes, and there is a near-zero chance of recovering a corrupt ZFS pool. So make sure you back up your unique data to another device or into the cloud. ...
I'd keep power consumption in mind. A pc in any form isn't particularly efficient.You do need to be careful about power consumption, but saying all PCs are inefficient is misleading. I have have been using the same Intel i3 system as a home server for about 12 years. It idles at 12-13W from the wall, and quite a bit of that is taken by 2 3.5" hard disks. Choosing a suitable motherboard and power supply is a big factor. Some motherboards with massive overclocking potential can have a horrible idle power draw. Some power supplies seem to be designed with no regard to their efficiency outside the range laid down in the 80PLUS spec.
I'd keep power consumption in mind. A pc in any form isn't particularly efficient.You do need to be careful about power consumption, but saying all PCs are inefficient is misleading. I have have been using the same Intel i3 system as a home server for about 12 years. It idles at 12-13W from the wall, and quite a bit of that is taken by 2 3.5" hard disks. Choosing a suitable motherboard and power supply is a big factor. Some motherboards with massive overclocking potential can have a horrible idle power draw. Some power supplies seem to be designed with no regard to their efficiency outside the range laid down in the 80PLUS spec.Well, compared to a relatively simple ARM processor optimised for super low power, even an i3 is quite a power hog. For comparison: the Qnap NAS I have consumes little over 7Watts max. including the hard drive according to the specs. But I'm sure this number is too high as I put a low power (2.9W idle), 5400 rpm hard drive in it.
Well, compared to a relatively simple ARM processor optimised for super low power, even an i3 is quite a power hog. For comparison: the Qnap NAS I have consumes little over 7Watts max. including the hard drive according to the specs. But I'm sure this number is too high as I put a low power (2.9W idle), 5400 rpm hard drive in it.
You've already claimed that "If the NAS crashes before it syncs pending metadata changes to disks (where metadata stands for file allocation tables of the beautiful COW file system), your entire ZFS pool will be lost with little prospect of recovery" which is demonstrably false, so I'm sorry, I don't have a lot of faith in your advice.
Why is the Btrfs file system as implemented by Synology so fragile?
February 29, 2024 by Phil Greenspun
We had a few seconds of power loss the other day. Everything in the house, including a Windows machine using NTFS, came back to life without any issues. A Synology DS720+, however, became a useless brick, claiming to have suffered unrecoverable file system damage while the underlying two hard drives and two SSDs are in perfect condition. It’s two mirrored drives using the Btrfs file system (the Synology default, though ext4 is also available as an option). Btrfs is supposedly a journaling file system, which should make this kind of corruption impossible. Yet searching the Internet reveals that Synology suicides are commonplace. Here’s one example that pins the blame on the SSDs being enabled as read/write caches (but given that the SSDs are non-volatile why isn’t the Synology software smart enough to deal with the possibility of a power outage even when read/write caching (seems to be the default) is enabled? The Synology web page on the subject says you need two SSDs (which I have) for “fault tolerance” and doesn’t mention that the entire NAS can become a brick after losing power for a few seconds).
Given that Synology has only one job, i.e., the secure storage of data, this strikes me as a spectacular failure of corporate mission.
Readers: Have you seen this kind of failure before? NTFS was introduced by Microsoft in 1993 and I’ve never seen it completely destroyed by a power interruption.
So, perhaps ZFS is the better COW file system compared to Btrfs, and maybe all the folks on the TrueNAS forum are mistaken about ECC memory and battery backups, along with all the TrueNAS guides being wrong. But what if they're not? What if wearing seatbelts really does save your life when you hit a pole at 40 miles per hour?
The full blog post is available here: https://philip.greenspun.com/blog/2024/02/29/why-is-the-btrfs-file-system-as-implemented-by-synology-so-fragile/