Jan 011999

dnswalk – a useful DNS tool

see also nslint.

When I was adding some new virtual domains, I had some trouble figuring out why only I could see the websites.  One of the tools I used to solve this problem was dnswalk.


The first step was to install dnswalk from the ports.  I followed the instructions found in the FreeBSD handbook for compiling port from CDROM.  You may want to see compiling ports from the internet.

In reality, here’s what I did:

cd /usr/ports/net/dnswalk
make install

Note that I have the entire ports tree on disk already.


For complete details on dnswalk, see man dnswalk.  See below for samples.  Remember to include the "." at the end of the domain name.  Otherwise you’ll get something like this:
su-2.02# dnswalk freebsdrocks.com
Usage: dnswalk domain
domain MUST end with a '.'


This section contains some samples of the first domains I could think of.
su-2.02# dnswalk freebsd.org.
Checking freebsd.org.
Getting zone transfer of freebsd.org. from ns1.iafrica.com...done.
SOA=implode.root.com    contact=hostmaster.freebsd.org
WARN: www4.freebsd.org CNAME www.se.freebsd.org: CNAME 
                                          (to freebsdwww.ludd.luth.se)
WARN: ns.lv.freebsd.org A no PTR record
WARN: ctm.freebsd.org CNAME ftp.uni-trier.de: CNAME 
                                          (to rzbsdi01.uni-trier.de)
WARN: ns.br.FreeBSD.org A no PTR record
BAD: de.freebsd.org NS dalx1.nacamar.net: unknown host
WARN: irc2.freebsd.org CNAME va.i-Plus.net: unknown host
WARN: irc3.freebsd.org CNAME irc.nocturnal.net: CNAME 
                                          (to nocturnal.net)
WARN: ns.th.freebsd.org A no PTR record
BAD: eu.freebsd.org NS dalx1.nacamar.net: unknown host
BAD: eu.freebsd.org NS server.zsb.th-darmstadt.de: unknown host
WARN: cvsup3.freebsd.org CNAME freebsd.lcs.mit.edu: CNAME 
                                          (to xyz.lcs.mit.edu)
WARN: cvsup4.freebsd.org CNAME mirrors.rcn.com: CNAME 
                                          (to gregory.dev.erols.net)
WARN: ftp3.freebsd.org CNAME ftp.cslab.vt.edu: CNAME 
                                          (to macadamia.cslab.vt.edu)
WARN: ftp6.freebsd.org CNAME mirrors.rcn.com: CNAME 
                                          (to gregory.dev.erols.net)
WARN: ampere.freebsd.org A no PTR record
0 failures, 12 warnings, 3 errors.

su-2.02# dnswalk daemonnews.org.
Checking daemonnews.org.
Getting zone transfer of daemonnews.org. from ns.hyp.net...done.
SOA=ns.hyp.net  contact=hostmaster.hypnotech.com
WARN: www.cn.daemonnews.org A no PTR record
WARN: www3.daemonnews.org CNAME www.vmunix.com: CNAME 
                                             (to vnode.vmunix.com)
0 failures, 2 warnings, 0 errors.

su-2.02# dnswalk freebsdrocks.com.
Checking freebsdrocks.com.
Getting zone transfer of freebsdrocks.com. from 
FAIL: Zone transfer of freebsdrocks.com. from newjersey.playgal.com 
                                          failed: couldn't connect
Getting zone transfer of freebsdrocks.com. from 
SOA=freebsdrocks.com    contact=ken.imgmkt.com
WARN: freebsdrocks.com A no PTR record
WARN: ken.freebsdrocks.com A no PTR record
WARN: www.freebsdrocks.com A no PTR record
1 failures, 3 warnings, 0 errors.