I’ve had this happen twice now when I install truenas from the latest ISO on a virtual server at Servarica where when you reboot, there is not webserver and no networking.
Here’s how I fixed the problem.
NOTE: Your IP addresses will be different than mine
Use the menu to enter the shell:
ip addr add 162.250.191.179/24 dev enX0
ip route add default via 162.250.191.1 dev enX0
Then exit the shell and pick the option to configure the gateway (and nameserver):and set it to the gateway assigned to your instance.
When you are finished, you’ll now have a GUI running at that IP address.
You can then restore the config from your backup, and then you’ll have to enter the public key to enable ssh login as truenas_admin since that isn’t stored in the config file.
Hopefully, this will save you a lot of time if you run into this case where the virtual machine instance isn’t able to find it’s IP address for some reason.