7 Remote virtual machines number as the screen index. The primary guest screen is selected with @1, the first secondary screen is @2, etc. The Microsoft RDP6 client does not let you specify a separate domain name. Instead, use domain\username in the Username: field – for example, @2\name. name must be supplied, and must be the name used to log in if the VRDP server is set up to require credentials. If it is not, you may use any text as the username. 7.1.9 VRDP video redirection Starting with VirtualBox 3.2, the VRDP server can redirect video streams from the guest to the RDP client. Video frames are compressed using the JPEG algorithm allowing a higher com- pression ratio than standard RDP bitmap compression methods. It is possible to increase the compression ratio by lowering the video quality. The VRDP server automatically detects video streams in a guest as frequently updated rectan- gular areas. As a result, this method works with any guest operating system without having to install additional software in the guest in particular, the Guest Additions are not required. On the client side, however, currently only the Windows 7 Remote Desktop Connection client supports this feature. If a client does not support video redirection, the VRDP server falls back to regular bitmap updates. The following command enables video redirection: VBoxManage modifyvm "VM name" --vrdevideochannel on The quality of the video is defined as a value from 10 to 100 percent, representing a JPEG compression level (where lower numbers mean lower quality but higher compression). The quality can be changed using the following command: VBoxManage modifyvm "VM name" --vrdevideochannelquality 75 7.1.10 VRDP customization With VirtualBox 4.0 it is possible to disable display output, mouse and keyboard input, audio, remote USB or clipboard individually in the VRDP server. The following commands change corresponding server settings: VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableDisplay=1 VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableInput=1 VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableUSB=1 VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableAudio=1 VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableClipboard=1 VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableUpstreamAudio=1 To reenable a feature use a similar command without the trailing 1. For example: VBoxManage modifyvm "VM name" --vrdeproperty Client/DisableDisplay= These properties were introduced with VirtualBox 3.2.10. However, in the 3.2.x series, it was necessary to use the following commands to alter these settings instead: VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableDisplay" 1 VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableInput" 1 VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableUSB" 1 VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableAudio" 1 VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableClipboard" 1 To reenable a feature use a similar command without the trailing 1. For example: VBoxManage setextradata "VM name" "VRDP/Feature/Client/DisableDisplay" 96