Virtual Machine installs Ubuntu three network modes

VMware offers three operating mode bridging (bridge), NAT (network address translation), and host-only (host mode).

NAT (network address translation)

In NAT mode, the virtual system needs to use the NAT (Network address translation) function to access the public network through the network where the host machine resides. In other words, using a NAT mode virtual system can access the physical host as a router to the Internet. The tcp/IP configuration information for the virtual system in NAT modeis provided by the DHCP server of the VMNET8 (NAT) virtual network and cannot be modified manually, so the virtual system cannot communicate with the other real hosts on the LAN.　　The biggest advantage of using NAT mode is that virtual system access to the Internet is very simple, you do not need to do any other configuration, only the host machine can access the Internet. This approach also enables two-way access to the host OS and guest OS. However, other machines within the network cannot access the Guest os,guest OS can access other machines within the network through the host OS with the NAT protocol. The NAT mode IP address configuration method is assigned an IP in VMware's virtual DHCP server, where the route is already set, which is pointing to 192. 168.138 . 1.　　If you want to use VMware to install a new virtual system, you can directly access the Internet without any manual configuration in the virtual system, it is recommended that you use NAT mode. In this way, there is a virtual network card Vmnet8 (by default), if you have a NAT server experience, the VMNET8 is equivalent to connect to the intranet network card, and the virtual machine itself is the equivalent of running on-line machine,　　The network card within the virtual machine (eth0) is independent of the vmnet8. You will find that in this way, VMware's own DHCP is loaded into the Vmnet8 interface by default, so that the virtual machine can use the DHCP service. More importantly, VMware comes with a NAT service that provides address translation from Vmnet8 to extranet, so this is a real NAT server running, but for virtual machines. Obviously, if you have only one extranet address, this approach is appropriate. 

Bridging (Bridge)

In bridging mode, VMware's virtual operating system is like a standalone host in a local area network (hosts and virtual machines are in a peer position), and it can access any machine on the network.　　In bridge mode, we often need to configure the virtual host IP address, subnet mask, etc. (note that the IP address of the virtual host and host IP address in the same network segment). The relationship between a virtual system and a host using bridged mode is like two computers connected to a hub, and for them to communicate they need to configure the IP address and subnet mask for the virtual system.　　If we need to establish a virtual server within the LAN, and provide services for local area network users, then choose the bridging mode. But for friends who want to do a variety of network experiments, this mode is not very suitable, because you can not control the network of virtual machines, it went directly out.

Host mode

　　

In the host mode, the real environment and the virtual environment are separated, in this mode, all the virtual systems can communicate with each other, but the virtual system and the real network are isolated. (Virtual systems and host machine systems can communicate with each other, which is equivalent to the two machines being interconnected by twisted-pair wires.) This should be the most flexible way to be interested in a variety of network experiments. Unlike NAT, the only difference is that, in this way, there is no address translation service, so by default, the virtual machine can only be accessed by the host.

Virtual Machine installs Ubuntu three network modes