nslookup bugs!!!

[Kevin Darcy]

Jim Reid wrote:

> >>>>> "Gerald" == Gerald Waugh <gerald at waugh.com> writes:
>
>     >> nslookup wants a reverse for that IP. You don't have it.  I
>     >> still see no reason why this 'demand' of nslookup s required,
>     >> but it is..
>
>     Gerald> Very useful though to test your reverse!  All IP's should
>     Gerald> have a working reverse.
>
> It is true that every IP address should have a working entry in
> in-addr.arpa so that reverse DNS lookups work. And it's also true that
> reverse lookups should be tested. However enforcing that policy with a
> critical prerequisite for a DNS lookup tool is spectacularly stupid
> and wholly inappropriate. What if the thing the lookup tool is being
> used to debug/test is reverse lookup for the name server it queries?
> If that server's IP address doesn't have a correct PTR record,
> nslookup fails which makes testing or checking with that "tool" almost
> impossible.

Not that I would ever encourage anyone to use nslookup for
DNS troubleshooting of course, but it _is_ possible to get around the
chicken-and-egg dilemma described above by starting up nslookup in
interactive mode pointing at some other (reverse-resolvable) server, then
switching back to the normal server using the "server" command. So
"almost impossible" I think is a bit of an exaggeration...


- Kevin