Tuesday, May 1, 2012

What is the difference between bridged, NAT and host-only networking? Which should I use?

A virtual machine in VMware Server, Workstation and Player can have virtual network cards that are "bridged", "NAT" or "host-only".
In Linux, a network of each type is created when running vmware-config.pl. In Windows, they are automatically created. If you didn't create them the first time vmware-config.pl was run, you can re-run it.
Comparison of the network types
Type Bridged NAT
(Network Address Translation)

Description The VM appears as if it was
a physical host on the network.
The VM hides behind the IP address of the VMware host. Other VMs in the same NAT network can access it directly. The VM can only access the VMware host and other VMs in the same host-only network
IP address The VM requires it's own IP address from the network it is supposed to  belong to.
The VM can have any private IP configured on the VMware host. 
Accessibility from network Same as a physical host Hides behind NAT, so port forwarding on the VMware host required if external access required Not accessible from external network unless routed via another VM with access to both external network and the same host-only network
Use cases  An always-on server hosted on VMware, or a virtual router or firewall  VMs intended for testing, or cases when the amount of IP addresses in the external network is limited. VMs intended for testing with no need to access the network, or VMs which will be protected by a firewall in another VM.
Other Known to have problems with some wireless chipsets especially with Linux, also with Windows Vista. NAT is really a host-only network with a default gateway (on the VMware host) that routes and NATs.  

No comments:

Post a Comment