8 VBoxManage • --usbehci on|off: This option enables or disables the VM’s virtual USB 2.0 controller see chapter 3.10.1, USB settings, page 49 for details. 8.7.4 Remote machine settings The following settings that affect remote machine behavior are available through VBoxManage modifyvm: • --vrde on|off: With the VirtualBox graphical user interface, this enables or disables the VirtualBox remote desktop extension (VRDE) server. Note that if you are using VBoxHeadless (see chapter 7.1.2, VBoxHeadless, the remote desktop server, page 91), VRDE is enabled by default. • --vrdeport default|ports: A port or a range of ports the VRDE server can bind to “default” or “0” means port 3389, the standard port for RDP. You can specify a comma- separated list of ports or ranges of ports. Use a dash between two port numbers to spec- ify a range. The VRDE server will bind to one of available ports from the specified list. Only one machine can use a given port at a time. For example, the option --vrdeport 5000,5010-5012 will tell the server to bind to one of following ports: 5000, 5010, 5011 or 5012. • --vrdeaddress IP address: The IP address of the host network interface the VRDE server will bind to. If specified, the server will accept connections only on the specified host network interface. • --vrdeauthtype null|external|guest: This allows you to choose whether and how authorization will be performed see chapter 7.1.5, RDP authentication, page 94 for details. • --vrdemulticon on|off: This enables multiple connections to the same VRDE server, if the server supports this feature see chapter 7.1.7, Multiple connections to the VRDP server, page 95. • --vrdereusecon on|off: This specifies the VRDE server behavior when multiple con- nections are disabled. When this option is enabled, the server will allow a new client to connect and will drop the existing connection. When this option is disabled (this is the de- fault setting), a new connection will not be accepted if there is already a client connected to the server. • --vrdevideochannel on|off: This enables video redirection, if it is supported by the VRDE server see chapter 7.1.9, VRDP video redirection, page 96. • --vrdevideochannelquality percent: Sets the image quality for video redirection see chapter 7.1.9, VRDP video redirection, page 96. 8.7.5 Teleporting settings With the following commands for VBoxManage modifyvm you can configure a machine to be a target for teleporting. See chapter 7.2, Teleporting, page 97 for an introduction. • --teleporter on|off: With this setting you turn on or off whether a machine waits for a teleporting request to come in on the network when it is started. If “on”, when the machine is started, it does not boot the virtual machine as it would normally instead, it then waits for a teleporting request to come in on the port and address listed with the next two parameters. 114