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

[nat]
VBoxManage modifyvm "VM name" --natpf1 "guestssh,tcp,127.0.0.1,2222,,22"
VBoxManage modifyvm "VM name" --natpf1 delete "guestssh"

VBoxManage natnetwork add --netname natnet1 --network "192.168.15.0/24" --enable
VBoxManage natnetwork add --netname natnet1 --network "192.168.15.0/24" --enable --dhcp on
VBoxManage natnetwork modify --netname natnet1 --dhcp on/off
VBoxManage natnetwork start/stop/remove --netname natnet1

VBoxManage natnetwork modify --netname natnet1 --port-forward-4 "ssh:tcp:[]:1022:[192.168.15.5]:22"
VBoxManage natnetwork modify --netname natnet1 --port-forward-4 delete ssh
VBoxManage setextradata global "NAT/win-nat-test-0/SourceIp4" 192.168.1.185
VBoxManage list natnetworks

[bridged]
[internal]
VBoxManage modifyvm "VM name" --nic<x> intnet
VBoxManage modifyvm "VM name" --intnet<x> "network name"

[host-only]
VBoxManage modifyvm "VM name" --nic<x> hostonly
VBoxManage hostonlyif create

[udp tunnel]
VBoxManage modifyvm "VM 01 on host 1" --nic<x> generic
VBoxManage modifyvm "VM 01 on host 1" --nicgenericdrv<x> UDPTunnel
VBoxManage modifyvm "VM 01 on host 1" --nicproperty<x> dest=10.0.0.2
VBoxManage modifyvm "VM 01 on host 1" --nicproperty<x> sport=10001
VBoxManage modifyvm "VM 01 on host 1" --nicproperty<x> dport=10002
and

VBoxManage modifyvm "VM 02 on host 2" --nic<y> generic
VBoxManage modifyvm "VM 02 on host 2" --nicgenericdrv<y> UDPTunnel
VBoxManage modifyvm "VM 02 on host 2" --nicproperty<y> dest=10.0.0.1
VBoxManage modifyvm "VM 02 on host 2" --nicproperty<y> sport=10002
VBoxManage modifyvm "VM 02 on host 2" --nicproperty<y> dport=10001

virtualbox network