[HAST] ZFS, many disks, write order

[Ben RUBSON]

Hello,

I plan to use HAST to synchronize a ZFS pool between 2 servers.
The ZFS pool has 3 RAID-Z2 VDEVs (8+2), + 3 spares.
+1 mirror for SLOG.
+1 mirror for L2ARC.
So a total of 37 disks (4TB each).
40Gb/s network bandwidth between the 2 servers.

Will I have to define each of the 37 disks/resources in hast.conf ?
Stupid question, but will this setup (with so many resources) work ?

Will write IOs be ordered on the secondary node in the same order (over all the 37 devices) as they occurred on the primary node ?
This of course to have the secondary node consistent, even after a power failure of the primary during a high IO load, leading into an import -F <poolname> on the secondary node.

In HAST, each resource seems to be "independent" from the others.
In DRBD, as an example, we can put several volumes in a same resource to guarantee write order over all the volumes (disks) of the resource.
Example :

resource r0 {
    volume 0 {
        device /dev/drbd0;
        disk /dev/c0v0;
    }
    volume 1 {
        device /dev/drbd1;
        disk /dev/c0v1;
    }
}

What about HAST then ?
Of course I would have liked to have my 37 disks as volumes in the same resource, as in the example above.

Thank you very much for your help !

Best regards,

Ben