The modprobe command ran without error or any feedback.
I found a Gentoo article that said to run this to see if IPv6 was active:
ip -6 addr show lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
The above result was what to expect if IPv6 is active. I read another article that stated it is no longer possible to disable IPv6 in Gentoo. This article was dated Jan, 2012.
However, a ping6 to a known v6 site responds, "connect: Network is unreachable". I had to install a package to get the ip command. My Sabayon system does not have a dig command, and I do not know what package to install to get it.
This ain't Ubuntu!
Tim