What you will advice for share zfs vm block with nappit ?
NFS share or iSCSI or ZFS over iSCSI
Seems Zfs over iSCSI don't use the zfs caching enable on the nappit server?
Something like this :
Disk <-> Nappit node <--- FC or iSCSI or ZFS-iscsi or nfs ---> Proxmox Node <-> VM on ZFS block
Here is a work around
Run one time as you did and when it's hang on "Removing old packages" (code is looping, check dpkg.log for check if loop happen), stop the install script.
vi the install script (mlnxofedinstall) and search for remove_old_packages function.
Then edit it...