Opmantek has released a new NMIS9 Virtual Appliance; it may be downloaded here:
https://dl-nmis.opmantek.com/Opmantek-20200822-VM9-Centos7.2003-2-64bit.ova


Release notes: Opmantek NMIS9 Virtual Appliance: Release Notes

Installation & Getting Started: Opmantek Virtual Machine: Installation and Getting Started