Configuring IXFR

3.23.1 Problem

You want to configure a slave (and its master) name server to use incremental zone transfers (IXFRs).

3.23.2 Solution

On a BIND 9 name server, you don't need any special configuration: BIND 9 slave name servers request IXFRs by default, and BIND 9 masters automatically create and maintain the journal files they need to respond to IXFR requests.

On BIND 8, however, you need to tell slave name servers to request an IXFR from a particular master in a server statement:

server 192.168.0.1 {
 support-ixfr yes;
};

You also need to configure the master to track changes to zones so it can respond to IXFR requests:

options {
 directory "/var/named";
 maintain-ixfr-base yes;
};

3.23.3 Discussion

Remember that IXFR only works with dynamically updated zones: the only changes that are logged in the master's journal are those made using dynamic updates. If you manually edit a zone data file, the changes won't make it into the journal. Moreover, a BIND 9 name server won't load a zone that's been edited by hand because it doesn't have the record of the latest change.

3.23.4 See Also

Section 3.24 to limit the size of the BIND 8 IXFR log file, Section 2.16 for instructions on making manual changes to a dynamically updated zone, and "Incremental Zone Transfer (IXFR)" in Chapter 10 of DNS and BIND.