Virtualbox runs “ NAT ENGINE” which receives the network packets from the guest VM and sends the packet to the host adapter to connect to the Internet. In NAT mode VM is well protected and VM uses host machine IP as a proxy to connect to the external world (Internet). This is the default mode when you create a Guest VM. VirtualBox Networking Modes Network Address Translation (NAT) The below table helps you understand how different networking options works and which one is suitable for you. VirtualBox has a built-in DHCP server that assigns an IP address to Guest VM based upon the mode you choose.

From VirtualBox GUI manager you can configure four network adapters and using VboxManage you can configure eight network adapters in total. In VirtualBox, each virtual machine can have up to 8 virtual network adapters. Configuring networking can be done in a few clicks but understanding what are different network modes available and you have to choose a model that satisfies your needs. Setting up networking is quite a difficult task in VirtualBox compared to other operations.

Virtualbox network settings centos