For problem determination, it is often important to collect debugging information which can be analyzed by Oracle VM VirtualBox support. This section contains information about what kind of information can be obtained.

Every time Oracle VM VirtualBox starts up a VM, a so-called release log file is created, containing lots of information about the VM configuration and runtime events. The log file is called VBox.log and resides in the VM log file folder, which is $HOME/VirtualBox VMs/VM-name/Logs by default.

When starting a VM, the configuration file of the last run will be renamed to .1, up to .3. Sometimes when there is a problem, it is useful to have a look at the logs. Also when requesting support for Oracle VM VirtualBox, supplying the corresponding log file is mandatory.

For convenience, for each virtual machine, VirtualBox Manager can show these logs in a window. Select a virtual machine from the machine list on the left and click Logs in the machine tools menu.

The release log file, VBox.log, contains a wealth of diagnostic information, such as Host OS type and version, Oracle VM VirtualBox version and build. It also includes a complete dump of the guest's configuration (CFGM), detailed information about the host CPU type and supported features, whether hardware virtualization is enabled, information about VT-x/AMD-V setup, state transitions (such as creating, running, paused, stopping), guest BIOS messages, Guest Additions messages, device-specific log entries and, at the end of execution, final guest state and condensed statistics.

In case of crashes, it is very important to collect crash dumps. This is true for both host and guest crashes. For information about enabling core dumps on Linux, Oracle Solaris, and macOS systems, refer to the following core dump article on the Oracle VM VirtualBox website:

http://www.virtualbox.org/wiki/Core_dump.

You can also use VBoxManage debugvm to create a dump of a complete virtual machine. See VBoxManage debugvm.

For network related problems, it is often helpful to capture a trace of network traffic. If the traffic is routed through an adapter on the host, it is possible to use Wireshark or a similar tool to capture the traffic there. However, this often also includes a lot of traffic unrelated to the VM.

Oracle VM VirtualBox provides an ability to capture network traffic only on a specific VM's network adapter. Refer to the following network tracing article on the Oracle VM VirtualBox website for information on enabling this capture:

http://www.virtualbox.org/wiki/Network_tips.

The trace files created by Oracle VM VirtualBox are in .pcap format and can be easily analyzed with Wireshark.