I have a VPS, ubuntu server 12.04 and for unknown reasons the network connection drops and I have to access my vps via the console and ifdown eth0 and ifup eth0. This brings the connection back up from about a few seconds to a few hours. I have run tail -F /var/log/syslog to monitor the log to see what happens at the point of drop and there is nothing unusual. The vps is running under virt-manager and the hardware is set to virtio. I have had linux friends look at my vps and they are unsure of what is the cause.