Since this issue was entered in Red Hat Bugzilla, the release flag has been
set to ? to ensure that it is properly evaluated for this release.
The behavior looks similar to bug 1119351. Please take a look at that bug and let us know if 'ping6 localhost' returns a successful response.
Marked this bug as Testblocker, because it blocked RHEV-Hypervisor register satellite 6 part testing.
According to comment 12, close this bug now, the bug 1119351 will trace ipv6 + katello-installer detail issue future.