NAME

dumpaxfr — capture a DNS zone transfer

SYNOPSIS

dumpaxfr [-46dx] [-p port] ⟨server⟩ ⟨zone⟩ [prefix]

DESCRIPTION

The dumpaxfr program sends a DNS AXFR zone transfer query to server for zone and saves the response in one or more files. The files are named like

prefix_server_zone_N.bin

You specify the server, zone, and prefix on the command line. The default prefix is xfer.

A zone transfer can consist of multiple DNS messages. Each message is written to a different file numbered N starting from 0.

The .bin suffix indicates that the file is a binary dump.

OPTIONS

-4: Use IPv4 only.
-6: Use IPv6 only.
-d: Print query and responses in a similar manner to dig(1).
-x: Print partially-parsed hex dump of responses.
-p port: Connect to port, which may be a service name or a port number. The default is the domain service, port 53.

BUGS

The dumpaxfr program incorrectly uses a read() timeout to detect the end of the zone transfer; it always finishes by reporting an error. The DNS protocol indicates the end of a zone transfer with a message whose last record is a second copy of the zone's SOA record. The dumpaxfr program does not parse responses (except when printing decoded messages) so it is too stupid to detect the end of the zone transfer correctly.

AUTHOR

Tony Finch ⟨dot@dotat.at⟩