Continuing in my venture to resolve the network issue on the virtual machine on my centos 6 host machine. The intermittent 'closing' off all network conditions can only be solved by service network restart My last thing I am going to try is to look at the different NIC devices I can use in virtual machine manager. The one i was using is the default I guess, virtio. The other options are e1000 ne3k_pci rtl8130 hypervisor default The e1000 has thousands of pages online about issues with centos, so will try that last. Gonna try hypervisor default. Other than changing this option I can find no reason for the network services to just go missing with nothing in the logs...they just disappear from the net.