Software update: PowerDNS recursor 3.1.3

The PowerDNS program is a DNS server with a database as back-end, making it easy to manage a large number of DNS entries. At the end of April of this year, the developers decided to release the two parts that make up PowerDNS, namely a recursor and an authoritative nameserver, separately. This allows for faster release of a new version, according to the developers. Version 3.1.3 of the PowerDNS recursor is now available with the following changes:

We are proud to release 3.1.3, compared to 3.1.2, this release again consists of a number of mostly minor bug fixes, and some slight improvements.

Thanks to some recent migrations, this release, is already powering over 40 million internet connections that we know of. We appreciate hearing about successful as well as unsuccessful migrations, please feel free to notify us (privately) of your experiences, good or bad.

Many thanks are again due to Darren Gamble who together with his team has discovered many misconfigured domains that do work with some other name servers. DNS has long been tolerant of misconfigurations, PowerDNS intends to uphold that tradition. Almost all of the domains found by Darren now work as well in PowerDNS as in other name server implementations.

Bug fixes:

• The MThread default stack size was too small, which led to problems, mostly on 64-bit platforms. This stack size is now configurable using the stack-size setting should our estimate be off. Discovered by Darren Gamble, Sten Spans and a number of others. Fixed in commit 868.
• Plug a small memory leak discovered by Kai and Darren Gamble, fixed in commit 870.
• Switch from the excellent nedmalloc to dlmalloc, based on advice by the nedmalloc author. Nedmalloc is optimized for multithreaded operation, whereas the PowerDNS recursor is single threaded. The version of nedmalloc shipped contained a number of possible bugs, which are probably resolved by moving to dlmalloc. Some reported crashes on hitting 2G of allocated memory on 64 bit systems might be solved by this switch, which should also increase performance. See commit 873 for details.

improvements:

• The cache is now explicitly aware of the difference between authoritative and unauthorized data, allowing it to deal with some domains that have different data in the parent zone than in the authoritative zone. Patch in commit 867.
• No longer try to parse DNS updates as if they were queries. Discovered and fixed by Jan Gyselinck, fix in commit 871.
• Rebalance logging priorities for less log cluttering and add IP address to a remote server error message. Noticed and fixed by Jan Gyselinck (commit 877).
• Add logging-facility setting, allowing syslog to send PowerDNS logging to a separate file. Added in commit 871.