SUMMARY: Success! Reverse lookups now work!

From: Rae, Scott (
Date: Fri Jul 14 2000 - 08:35:28 CDT

I received a couple more responses - thanks to Craig Russell and Richard

Although I'd already looked at it many times, today I took another look at
named.boot, and found that the entry was wrong. Whoever put
this line in, put the octets of the subnet in the correct order, not in

        The subnet is 10.100.7.

        The original record said:


        so I changed it to:


        and now reverse lookups for that subnet work!

No doubt now that I resolved that one I'll be given lots of DNS problems to
look at.

What a great list this is.

mmary of other responses:

> I got several very useful replies to my question, which is copied at
> the bottom of this message. Unfortunately I was not able to resolve the
> problem. After spending a few hours on it, the user said that things were
> working well enough for now (they don't NEED to do reverse lookups at
> present), and my boss said I had to go and do other things anyway....
> Many thanks to Robert Hayne, Todd Herr, Philip Ordinario, Claudio
> Cuestas, Adam and Christine Levin, Dave McFerren, Rodney Wines, Richard
> Butler, Hoang Nguyen and Peter Gutmann for their help.
> The main suggestions were:
> 1. You've got to update the serial number, by incrementing it, each
> time you update a named file, and then signal your named process
> to re-read your named file by HUP'ing the named process:
> kill -HUP <named process PID>
> A good format to use for your serial numbers is:
> where YYYY is the year the file was changed
> MM is the month
> DD is the date
> XX is a two digit number (you probably won't make 100 changes
> per day)
> So, the first time you modify a file today, your serial number
> in that file should be set to:
> 2000071101
> if you mod it again today, set it to 2000071102, and so on.
> 2. Run nslookup query without any hostname nor ip address to see if the
> correct DNS server responds.
> 3. Check that a PTR record exists in the named.rev file or equivalent.
> No doubt this one will come back to haunt me!


Original Post:

> > Hello,
> >
> > I'm having problems doing reverse lookups of two
> hosts that have
> > recently been added to DNS database files. There
> are PTR records for the
> > hosts in the named.rev file, and we can do reverse
> lookups for other
> hosts.
> > The PTR records for the new hosts look good to me,
> though I must confess I
> > have not done a lot of DNS things.
> >
> > I have followed the DNS troubleshooting guide in
> "NEtworking Unix"
> > by Salim Douba, but I am still having problems.
> When I try the lookup I
> get
> > the "Non-existent host/domain" error, but of
> course the host and domain do
> > exist.
> >
> > Does anyone have any ideas? I've run out of
> things to look at. One
> > thing I don't fully understand is the serial
> numbers of the database
> files.
> >
> > Any help would be much appreciated.

U BEFORE POSTING please READ the FAQ located at
. and the list POLICY statement located at
A To submit questions/summaries to this list send your email message to:
A To unsubscribe from this list please send an email message to:
E and in the BODY type:
R unsubscribe sun-managers
S Or
. unsubscribe sun-managers original@subscription.address
L To view an archive of this list please visit:

This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:14:11 CDT