A. You probably configure your VMware Workstation VMs to use Bridged networking. With bridged networking, the virtual network switch created by VMware Workstation bridges whatever network the host uses to the VM. By doing this, whatever IP address range used by your host is also used by your VMs.
This configuration works great if your host doesn't move around a lot, but it can cause problems when your host's subnet changes. This becomes a very big problem when you've assigned static IP addresses to VMs.
You can get around this problem by connecting VMs to Workstation's NAT interface (VMnet8) instead of its bridged network (VMnet0). VMs connected to this network are given a special subnet—the actual subnet is randomly generated the first time you launch the Virtual Network Editor. That subnet only changes when you specifically configure it to. VMs in that network needn't suffer a subnet change when the host does.
Be aware that NAT comes with its own limitations. The host will always be able to connect to VMs on the NAT network, but other computers won't. If you need other computers to connect to VMs on the NAT network, create port forwarding rules under NAT Settings. These rules, which are set by the individual TCP or UDP port, will let external computers talk with VMs in the NAT network.
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