At around 7.35AM this morning, the University lost access to the IPv6 Internet.
You will experience this as slow responses from IPv6-enabled websites (such as Facebook), and you will be unable to access IPv6-only resources (such as ipv6.google.com).
The problem was reported to TENET earlier today, and we're told that this is as a result of multiple fibre optic breaks on SANReN's network. There is currently no estimated time-to-restore. However, the fact that we have working IPv4 suggests that there's more to it than simply fibre breaks.