VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.
Some of the features of VirtualBox are:
- Modularity. VirtualBox has an extremely modular design with well-defined internal programming interfaces and a client/server design. This makes it easy to control it from several interfaces at once: for example, you can start a virtual machine in a typical virtual machine GUI and then control that machine from the command line, or possibly remotely. VirtualBox also comes with a full Software Development Kit: even though it is Open Source Software, you don't have to hack the source to write a new interface for VirtualBox.
- Virtual machine descriptions in XML. The configuration settings of virtual machines are stored entirely in XML and are independent of the local machines. Virtual machine definitions can therefore easily be ported to other computers.
* VMM: reduced IO-APIC overhead for 32 bits Windows NT/2000/XP/2003 guests; requires 64 bits support (VT-x only; bug #4392)
* VMM: fixed double timer interrupt delivery on old Linux kernels using IO-APIC (caused guest time to run at double speed; bug #3135)
* VMM: reinitialize VT-x and AMD-V after host suspend or hibernate; some BIOSes forget this (Windows hosts only; bug #5421)
* VMM: fix loading of saved state when RAM preallocation is enabled
* BIOS: ignore unknown shutdown codes instead of causing a guru meditation (bug #5389)
* GUI: never start a VM on a single click into the selector window (bug #2676)
* Serial: reduce the probability of lost bytes if the host end is connected to a raw file
* VMDK: fix handling of split image variants and fix a 3.0.10 regression (bug #5355)
* VRDP: fixed occasional VRDP server crash
* Network: even if the virtual network cable was disconnected, some guests were able to send / receive packets (E1000; bug #5366)
* Network: even if the virtual network cable was disconnected, the PCNet card received some spurious packets which might confuse the guest (bug #4496)
* Shared folders: fixed changing case of file names (bug #2520)
* Windows Additions: fix crash in seamless mode (contributed by Huihong Luo)
* Linux Additions: fix writing to files opened in O_APPEND mode (bug #3805)
* Solaris Additions: fix regression in guest additions driver which among other things caused lost guest property updates and periodic error messages being written to the system log