[Pdns-dev] PowerDNS Recursor 3.1.2 released!
bert.hubert at netherlabs.nl
Mon Jun 26 08:28:08 CEST 2006
After extensive testing, we are proud to announce PowerDNS Recursor version
Compared to 3.1.1, this release consists almost exclusively of bug-fixes
and speedups. A quick update is recommended, as some of the bugs impact
operators of authoritative zones on the internet. This version has been
tested by some of the largest internet providers on the planet, and is
expected to perform well for everybody.
Changelog with clickable links describing each change on
http://doc.powerdns.com/changelog.html , text version:
Many thanks are due to Darren Gamble, Stefan Schmidt and Bryan Seitz who
all provided excellent feedback based on their large-scale tests of the
* Internal authoritative server did not differentiate between 'NXDOMAIN'
and 'NXRRSET', in other words, it would answer 'no such host' when an
AAAA query came in for a domain that did exist, but did not have an
AAAA record. This only affects users with auth-zones configured.
Discovered by Bryan Seitz, fixed in commit 848.
* ANY queries for hosts where nothing was present in the cache would not
work. This did not cause real problems as ANY queries are not reliable
(by design) for anything other than debugging, but did slow down the
nameserver and cause unnecessary load on remote nameservers. Fixed in
* When exceeding the configured maximum amount of TCP sessions, TCP
support would break and the nameserver would waste CPU trying to
accept TCP connections on UDP ports. Noted by Bryan Seitz, fixed in
* DNS queries come in two flavours: recursion desired and non-recursion
desired. The latter is not very useful for a recursor, but is
sometimes (erroneously) used by monitoring software or loadbalancers
to detect nameserver availability. A non-rd query would not only not
recurse, but also not query authoritative zones, which is confusing.
Fixed in commit 847.
* Non-standard DNS TCP queries, that did occur however, could drive the
recursor to 100% CPU usage for extended periods of time. This did not
disrupt service immediately, but does waste a lot of CPU, possibly
exhausting resources. Discovered by Bryan Seitz, fixed in commit 858,
which is post-3.1.2-rc1.
* The PowerDNS recursor did not honour the rare but standardised 'ANY'
query class (normally 'ANY' refers to the query type, not class),
upsetting the Wildfire Jabber server. Discovered and debugged by
Daniel Nauck, fixed in commit 859, which is post-3.1.2-rc1.
* Everybody's favorite, when starting up under high load, a bogus line
of statistics was sometimes logged. Fixed in commit 851.
* Remove some spurious debugging output on dropping a packet by an
unauthorized host. Discovered by Kai. Fixed in commit 854.
* Misconfigured domains, with a broken nameserver in the parent zone,
should now work better. Changes motivated and suggested by Darren
Gamble. This makes PowerDNS more compliant with RFC 2181 by making it
prefer authoritative data over non-authoritative data. Implemented in
* PowerDNS can now listen on multiple ports, using the local-address
setting. Added in commit 845.
* A number of speedups which should have a noticeable impact,
implemented in commits 850, 852, 853, 855
* The recursor now works around an issue with the Linux kernel 2.6.8, as
shipped by Debian. Fixed by Christof Meerwald in commit 860, which is
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