Let’s say you need to spin up a VirtualBox machine that requires a Class A IP for its host-only network. All the sudden, it halts the provisioning process and prints out the following message:

The IP address configured for the host-only network is not within the
allowed ranges. Please update the address used to be within the allowed
ranges and run the command again.

  Address: 10.135.135.100
  Ranges: 192.168.56.0/21

Valid ranges can be modified in the /etc/vbox/networks.conf file. For
more information including valid format see:

  https://www.virtualbox.org/manual/ch06.html#network_hostonly

You glanced at the suggested documentation, but since you are in a hurry missed the part where it clearly says how to enable all IP ranges for the host-only adapters. So, you just google it, and here we are :)

Step-by-Step solution

1. As super user (root or sudoer), ensure the /etc/vbox directory exists
2. As super user (root or sudoer), write * 0.0.0.0/0 ::/0 into the /etc/vbox/networks.conf file
3. Done. No restart is required

# tl;dr give me the code!
$ sudo mkdir /etc/vbox
$ echo '* 0.0.0.0/0 ::/0' | sudo tee /etc/vbox/networks.conf

Side note

It might look dumb that I wrote a post about something that is already documented. But I was that hasty person googling this issue hoping to get lucky back then, so I felt the need to spell it out to anyone else in the same situation. “Homies help homies, always.”

PS: The * at the beginning of every entry in the networks.conf file is mandatory. In my rush, I overlooked it and it gave me a mild headache for free.

Last modified on 2022-01-09