Changing virtualbox dhcp address range for vagrant VMs

It seems to be impossible to change the default vagrant address range from 10.0.x.0/24 to anything else for virtualbox VMs. This is virtualbox's fault. You can change the address range for individual VMs like this, note you need to shut it down first:

$ VBoxManage list vms
"ubuntu-xenial-16.04-cloudimg" {ea0e8dfd-55b9-48c7-b568-e933d0853762}
$ VBoxManage modifyvm "ubuntu-xenial-16.04-cloudimg" --natnet1 "192.168.23.0/24"

But that's just that VM, when you tear it down or create a new one with vagrant it will still come up with 10.0.x.0. You can of course also specify a specific IP in your Vagrantfile, but then you need to do that for every box.

I think you should be able to use this feature to create a new nat network with the new address range, and then tell vagrant to use that network in your Vagrantfile. But I haven't actually tried this because it means everyone using your Vagrantfile has to then have the same setup.

Really what needs to happen is that VirtualBox should have a global setting for their inbuilt NAT that allows you to change the address range.