ZFS Central Storage

neat idea- sure.

design as suggested- relatively simple.

Making it work in real life without connectivity loss on failover, data loss, have engineering capability for the MANY edge cases, able to actually support a production environment- practically impossible. this as a DIY will cause you pain.
 
Maybe i'm missing a benefit here, but this seems like it would be attempting to use ZFS in a way that is already implemented (better) in Ceph.

Alternatively, if you're just looking for redundant ZFS, why not simply set up a zfs-send/receive job in Cron instead of multi-homing the disk shelves?

IMHO, attempting to implement SAN architecture is a bit outdated nowadays.
 
Maybe i'm missing a benefit here, but this seems like it would be attempting to use ZFS in a way that is already implemented (better) in Ceph.

Alternatively, if you're just looking for redundant ZFS, why not simply set up a zfs-send/receive job in Cron instead of multi-homing the disk shelves?

IMHO, attempting to implement SAN architecture is a bit outdated nowadays.

Ceph requires 4-5 nodes to be a real HA setup. We have a full ceph cluster setup inhouse, I wouldn't even consider it without atleast 4 nodes.

Money is a factor as well. zfs-send/receive requires front ends with the same amount of disks. With central storage we only have to buy one set of disks.
 
neat idea- sure.

design as suggested- relatively simple.

Making it work in real life without connectivity loss on failover, data loss, have engineering capability for the MANY edge cases, able to actually support a production environment- practically impossible. this as a DIY will cause you pain.

Its would be SAS connectivity, it should be a simple zfs import on failovers. I do get what your saying to a degree.
 
I'd also love such a setup, but it lacks a lot with respect to a HA SAN even without another datacenter node.

There is also "real" products you can buy that claim they worked it out:

https://zstor.de/en/zstor-ha-cluster-designs-e.html

Yea I have looked at those in the past, but when you get down to the nitty gritty they came in with a price tag pretty much the same as our Nimble iSCSI array's. Only so many of our customers can afford such a setup. We are trying to come up with a bit more cost effective solution.
 
Ceph requires 4-5 nodes to be a real HA setup. We have a full ceph cluster setup inhouse, I wouldn't even consider it without atleast 4 nodes.

Money is a factor as well.

Most of those in the project's examples had 4+ shelves full of disks.

If you can afford to drop thousands on disk, you can afford a couple hundred for a ceph node.

I love ZFS. I use it wherever it makes sense. This just seems like a use case that wouldn't make sense for proxmox, and doesn't seem like it would be that great of a solution anywhere really... it's like using a hammer to pound screws.