Microserver gen 8 with SATA controller in AHCI mode.
Had OMV 4 running for some time from USB flash drive plugged into internal slot and 4 data disks in the bays (ZFS). The USB flash drive has just failed.
Decided to install fresh OMV 5 onto an SSD drive plugged into the ODD SATA slot, keeping the data disks as they were. Installed OMV 5 on the SSD, the system would boot from it with the 4 disks unplugged. Followed a guide to install and configure grub on a USB flash drive in order to boot from it but point to the OS on the SSD drive and plugged back in the 4 disks.
Now OMV it's seeing the disks, but, just tried installing ZFS plugin among others and it failed, so cannot import the ZFS pool etc. nor can retry the update process as the update packages are not available in the GUI anymore.