network: destination host unreachable

try DHCP for the network interface

sudo /etc/init.d/networking restart && sudo dhclient

first things first. can you ping 192.168.56.1 ? if so then you have an IP connection to the router, set this as your default route. otherwise try pinging 192.168.56.255 (broadcast) to see on what address you might get replies. see arp -a to check what addresses you can find.

can you ping 8.8.4.4 (google) after changing the default route? if so you have internet access. if not check the router.

can you ping www.google.com? if not you might have a dns problem

do you get results from nslookup www.google.com ?

check the network card of the VM in the virtualization software. is it in "bridged" mode? or in a "NAT" or "host-only" mode?

in the last case change it to bridged and try $sudo dhclient

in the first case, see if the hypervisor itself can ping to its default gw and 8.8.4.4