Like my subject, i want share about how to communicate two host in virtualbox. This is very simple. Lets do it:
1. Open your virtualbox.
2. Make sure you have 2 host in your library, for example you have windows XP and windows 7.
3. Set ip address in XP and 7 in the same network. Like this: Windows xp configured by 192.168.1.1/24 and windows 7 is 192.168.1.2/24.
4. Make sure network adapter in 2 host set by Internal Network/Jaringan Internal. For detail, see picture below.