virtualbox.org

I've set an Win Xp guest and install there an oracle db 11g. It works fine when I'm taring to connect to it using sqlDeveloper on guest machine (system@//10.0.2.15:1521/orcl). But from host machine it does not work ;/
Guest is behind NAT so I've set a forward role like [VBoxManage modifyvm "winXp" --natpf1 "orclForward,tcp,,1521,,1521"], but it not working. When i run wireshark on guest i can see SYN tcp packages while taring to connect (system@//loclahost:1521/orcl or system@//127.0.0.1:1521/orcl) but there is no ACK response and I'm not sure if it is fault of VB or db configuration.

You would probably have better results using host-only instead of NAT for this.
Add a second adapter set to NAT if you want the Internet in the guest.