[GTALUG] Which Distro is Best for Running a ZFS-on-Linux Fileserver.

[Scott Sullivan]

On 2018-08-29 11:43 PM, Amos H. Weatherill wrote:
> Scott,
> 
> My reasoning for / on ZFS is pretty Simple ... the machine that is 
> becoming my first NAS only has 4 SATA Ports, so I can't afford to Waste 
> one on a boot drive.

Recommended best Practice is to use ZFS with whole disks. That said, 
most of the arguments for that are 'because the manual says so', 
'because zfs datasets are far more flexible then partitions' and 
references to Solairs taking advantage of disk caches. I throw that all 
out the windows in favor of doing at rest encryption, with whole luks 
partitions(*).

My more practical argument is choice of MBR vs GUID partitioning. The 
latter is just cleaner (and the default when ZFS manages the disk), and 
works well with large disks (>2TB).

But if your booting from that disk, you either need to be:
     "BIOS / CSM" + MBR + /boot
or
     UEFI + GUID + "biosboot (partition)" + /boot

Either of those makes for some lopsided partitioning, compared to the 
remainder of your data disks. A work around is to use a USB drive for 
your /boot. But in general your creating a more complex setup to 
maintain either way.

Not knowing what hardware your using, if you have PCIe slots additional 
sata ports can be had for a low a $10/port.

I've been using the Syba / IOCrest cards for a variety of needs, 
including ZFS arrays without issue.

https://www.newegg.ca/Product/Product.aspx?Item=N82E16816124064

> For Distro, I think I'll go with Fedora, as long as the / on ZFS guide 
> is sufficiently detailed.

Fedora was not one of the ones I listed as having a guide to do rootfs 
on ZFS. If you found one, can you post the link?

I'd also not recommend fedora in general for a NAS. CentOS would be a 
more dependable choice. LTS Ubuntu would be more reasonable as they 
ship(**) ZFS and support rootfs on it.


===
* Native encryption in ZFS was added after the OpenZFS split from 
Sun/Oracle. So work to re-added it has been happening for a while. We're 
likely to see a stable version in the v0.8.x series.

** This is due to their adoption of a minority legal opinion about 
compatibility of the CDDL and GPL licenses that has not been tested in 
court.
https://blog.ubuntu.com/2016/02/18/zfs-licensing-and-linux
https://sfconservancy.org/blog/2016/feb/25/zfs-and-linux/

-- 
Scott Sullivan