[Pdns-users] ixfr support for slaves with large zones

Kenneth Marshall ktm at rice.edu
Thu Mar 19 17:21:29 UTC 2009

On Thu, Mar 19, 2009 at 03:52:34PM +0100, Sean Boran wrote:
> Hi,
> I have a pdns slave to a very large zone (and I do not have administrative
> access to the master server), where the serial changes almost every second.
> This means that the entire zone keeps being sent. The ixfr protocol, seems
> to be the solution in that only the changes to a zone would be propagated.
> http://www.dns.net/dnsrd/rfc/rfc1995.html
> However, when I search for pdns support for ixfr I dind't much much execpt a
> patch two years ago to answer ixfr queries and force full transfers.
> So ixfr is not yet supported, is that correct?
> Thanks in advance,
> Sean Boran


That is correct, IXFR is not supported so pdns falls back to using
AXFR for the transfer. I had posted a patch to at least allow for
the DB update process to be optimized a few years ago. This kept
the DB backend from being overrun by the AXFR updates. It sounds
like your best bet is to script/cron the update to occur periodically
instead of every second to manage the I/O. Good luck.


More information about the Pdns-users mailing list