Autoaxfr -- A wrapper script for axfr-get

A wrapper script for axfr-get. This file documents autoaxfr version 1.2.

The main distribution site for autoaxfr is The DNS system this was designed for, tinydns, is available at A useful related site is




This program might be useful to you if you are running tinydns but must also fetch some zones with the (insecure) zone transfer protocol.

Basically, this program lets you emulate the functionality of bind's ``type slave'' zones with a ``masters'' list of IP addresses.

It is designed to run as a daemon that periodically wakes up to do zone transfers. It leaves the current zones in a well known directory for you to incorporate into tinydns' data.cdb by hand, with a crontab, or other means.

Currently, autoaxfr is completely passive and does not have a mechanism to notify another program when the zones it fetches have changed.

To use this program you need djbdns, ucspi-tcp, and daemontools.


Copy the autoaxfr script to /usr/local/bin. Modify the first line to point to where your perl 5.x lives, if it isn't in /usr/bin.

Run autoaxfr-conf like so:

        autoaxfr-conf acct logacct DIR

Where acct is usually a 'autoaxfr' account you've created just for autoaxfr, logacct is the 'dnslog' account you probably set up for use with djbdns, and DIR is usually /etc/autoaxfr.

If you didn't put autoaxfr in /usr/local/bin, modify DIR/run to run it from the correct location.

If the axfr-get and tcpclient programs aren't in the system's default path, modify DIR/run to add the appropriate directory to the PATH environment variable.

Then you can put a symlink in /service to DIR and autoaxfr will run under the svscan just like tinydns.


Say you have this in your bind named.conf:

        zone "" {
                type slave;
                masters {;; }

You get the same effect by doing this:

        echo >  DIR/root/slaves/
        echo >> DIR/root/slaves/

Autoaxfr will try to do zone transfers for from those two IP addresses (using the second only if the first fails). When transferred, the zones are placed in a file of the same name in the DIR/root/zones/ directory.

Autoaxfr will honor the refresh and retry times in the zone's SOA and update the zones with axfr-get as appropriate.

If you'd like to axfr a root zone, use @ as the file name. Autoaxfr will translate that into the ``.'' domain name when calling axfr-get.

What Next?

You have to get the zone data into tinydns somehow.

This is the Makefile I use in /etc/tinydns/root. I place my zone data in mydata. The Makefile copies the slave zone data from DIR/root/zones and places it in axfrdata. The two are then concatenated into data and transformed into data.cdb. I run this makefile from root's crontab every 5 minutes.

        data.cdb: data
        data: mydata axfrdata
                cat $^ > $@
        axfrdata: /service/autoaxfr/root/zones/*
                sort -u $^ > $@

Bugs (or features?)

No attention is paid to slave zone SOA expire time. Autoaxfr will keep trying to transfer a zone until you remove it from DIR/root/slaves. It will never delete a file from DIR/root/zones.

On the same token, if you delete a file in DIR/root/slaves, you must also delete the file in DIR/root/zones.

I am assuming that axfr-get does auditing of the zones it receives and doesn't allow garbage for other zones to pollute its output. Be warned that I haven't actually verified that this is the case!