To figure out what's going on, you can check the iptables for any firewalling with the command iptables -L -v And ports that are listening for incoming connect

To figure out what's going on, you can check the iptables for any firewalling with the command iptables -L -v And ports that are listening for incoming connections with netstat -ltp For example, it might be that you're listening for connections on a different interface (ip address) than the virtualised machine is connecting to.