if you want one LAN for one WAN, you could do it with 5 ClearOS. One as a KVM hypervisor running 4 instances of ClearOS. With one ClearOS you won't get separation of your LAN's. Even WAN's won't separate if one fails, but otherwise source-based routing should work.

The potential benefits of 2 or 3 is that you could use dedicated hypervisor o/s. I have one proxmox server, a server which was ClearVM but we did things to break ClearVM and now just run it as Centos with KVM command line, and I have ClearOS running KVM/Kimchi.

I have no idea about this set up. If you have four ports on the ISP box and they carry different traffic, then you'll need 4 NIC's in ClearOS unless you can redirect all the ISP traffic over VLANS on a single port.

ClearOS is not really designed to tie a WAN port to a LAN port and port forwarding operates on all WAN ports at the same time.

I think hypervisors often have the ability to pass through NIC's and ports. From Googling, Xen does - https://www.google.com/search?q=xen+passthrough+wifi+nic.

From your link, there are a couple of glitches installing KVM in ClearOS but I run it. I also sometimes use Kimchi, but it is relatively old and there is an annoying bug (if you upload an iso, it ends up with the wrong permissions so you have to change them before you can use them). You can also use the graphical desktop and Virtual Machine Manager to manage KVM. There is a howto in our knowledgebase. The command line isn't too bad either. In ClearOS you can also run VirtualBox.

I've patched syswatch and there is a version now available for testing. Note this only affects people with an interface which get its IP address by DHCP . To test, please do a: