Ok I’m feeling quite sad (frustrated) now.
After getting my UI up and running, I noticed that I cannot access my crashplan-pro container’s UI (on port 5800).
I then checked out the Hosts view, and it shows the host as Disconnected.
Back to this forum, and I found this thread which did not help, but the opening post mentions that a restart of his FreeNAS VM eventually reconnects the Host.
So I restarted my FreeNAS VM, and now I am once again unable to access my Rancher UI on port 8080, and the docker commands once again just wait and wait forever!!!
A ros config export shows that the network interface is still as per my last edit (no custom mtu setting there).
What on earth is going on here?