I want to seriously work with IPv6 and not have stray IPv4 functions messing with me. So in /etc/sysconfig/network, I commented out NETWORKING=yes. I have NETWORKING_IPV6=yes. In /etc/sysconfig/network-scripts I altered ifcfg-eth0, setting BOOTPROTO=none. That was enough for eth0 to only have IPv6 working on it (have IPV6INIT=yes and IPV6_AUTOCONF=yes). But lo had IPv4. So I commented out all of the IPV4 lines in ifcfg-lo. Still have IPv4 on lo. How do I disable that? Yes, I did an service network restart after changing ifcfg-lo.