BIND 9.11

2017-07-11 - News - Tony Finch

The central DNS servers have been upgraded from BIND 9.10 to BIND 9.11, which has a number of new features a few of which are particularly relevant to us.

On the authoritative servers, the minimal-any anti-DDOS feature was developed by us and contributed to isc.org. Happily we no longer have to maintain this as a patch.

On the recursive servers, there are a couple of notable features.

Firstly, BIND 9.11 uses EDNS cookies to identify legitimate clients so they can bypass DDoS rate limiting. Unfortunately EDNS options can encounter bugs in old badly-maintained third-party DNS servers. We are keeping an eye out for problems and if necessary we can add buggy servers to a badlist of those who can't have cookies.

Secondly, we now have support for "negative trust anchors" which provide a workaround for third party DNSSEC failures. Fortunately we have not so far had significant problems due to the lack of this feature.