Android ADB unable connect with IP address I have successfully installed Android OS in Oracle virtual box, but I have one problem: I cannot connect to ADB in the Android OS virtual box.

In my Network settings in virtual box:  


When I select host-only Adapter option, I can connect with ADB, but I have no Internet connection.
When I select NAT, I cannot connect with ADB, but I have Internet connection.


How do I fix this?
If you use NAT you must add the right forwarding rule:
Go to your network configuration.
Select NAT, put PCnet-FAST III as adapter, and deny in mode.
Then click in the button to add the rules and add a rule for TCP where the host and guest ports are 5555.

Always the most sneaky part is the network configuration of the VM, try with this one. If you still have issues check this tutorials:
Speeding up Android development with Android-x86 and VirtualBox