Created attachment 1754808 [details] screen shot When using developer user and creating vm from template I chose to customize vm settings and saw I was unable to add new network due to issue with fetching network attachment definitions (see attachment).
The error is telling it has no "Network Attachment Definitions" available so it cannot continue. Maybe the error message itself is confusing, It looks like it has problem to fetch the NAD. It looks the 4.6 error message is more clear, don't know why it's changed. - error message on 4.7 "Error fetching available Network Attachment Definitions. Contact your system administrator for additional support." - error message on 4.6 "No Network Attachment Definitions available. Contact your system administrator for additional support."
Now the error message is "No Network Attachment Definitions available. PXE capable Network Attachment Definition is required to successfully create this virtual machine. Contact your system administrator for additional support." Looks good.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: OpenShift Container Platform 4.8.2 bug fix and security update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2021:2438