Hello! I know this has been dormant for a very long time, but I figured out the answer, and wanted to post to make sure that others finding this found a solution.
OPNsense Version: 24.7.5-amd64
While configuring the OpenVPN instance, there is a toggle in the top left "Advanced Mode". Toggling this will show an additional drop down in the "Trust" section that has the CA to use.
OPNsense Version: 24.7.5-amd64
While configuring the OpenVPN instance, there is a toggle in the top left "Advanced Mode". Toggling this will show an additional drop down in the "Trust" section that has the CA to use.