List all virtual machines on this system using the vboxmanage list vms command:

user % vboxmanage list vms

"OpenBSD" {f3a856cd-ff01-4cdb-8559-85a97e432e9b} "CORE"{17a10a47-df81-4c65-b1a1-b23a6e4486c4} "IMUNES"{f241611c-4e63-4ec8-a520-23118cd20ee7}

Display running virtual machines:

vboxmanage list runningvms

To list all virtual machines with all settings that are on current host, use following command:

vboxmanage list vms -l

The amount of output produces by this is comparable to the show tech-support command.

Power on a virtual machine without the VBox GUI popup window in X - this is called headless, with the vboxmanage startvm command:

user % vboxmanage startvm OpenBSD --type headless

Waiting for VM "OpenBSD" to power on... VM "OpenBSD" has been successfully started.

And if you do it wrong:

user % vboxmanage startvm OpenBSD

Waiting for VM "OpenBSD" to power on... VBoxManage: error: The virtual machine 'OpenBSD' has terminated unexpectedly during startup because of signal 6 VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component MachineWrap, interface IMachine

Here it failed to start because probably the --type headless option has been forgotten.

Check if the virtual machine has started:

ping openbsd
PING openbsd (198.51.100.232) 56(84) bytes of data.
64 bytes from openbsd (198.51.100.232): icmp_seq=1 ttl=64 time=0.277 ms
^C
--- openbsd ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms 

Verify the current status of running vms by using the vboxmanage list runningvms command:

user % vboxmanage list runningvms "OpenBSD" {f3a856cd-ff01-4cdb-8559-85a97e432e9b}

Finally if the work has been done, power off the virtual machine using the vboxmanage controlvm command:

user % vboxmanage controlvm OpenBSD poweroff 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

For a CLI jokey it is the best way to operate and manage virtual machines. If you want the kitchen-sink command then just type in and hit enter:

VBoxManage

The version of VBox that has been used:

Oracle VM VirtualBox Command Line Management Interface Version 6.0.14_Gentoo
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