VirtualBox Scroll Up/Down Guest Terminal

Solution 1:

If you'd like to scroll up/down in VirtualBox terminal window, use please the combination key: Shift+PageUp/PageDown

For leave terminal window, just press the right Ctrl.

Solution 2:

If you are on a Mac with no Page Up/Page Down keys, press Shift+Fn+Up Arrow or Shift+Fn+Down Arrow

Solution 3:

Not exactly what you asked, but it is a usable workaround: after starting up your VirtualBox, connect to it with a ssh client like putty. You can then work and scroll in the ssh client, instead of using the VirtualBox terminal.

With Virtualbox, the guest should be connected to the network using Bridge Adapter instead of NAT for connecting via SSH with Putty.