[comp.sys.sun] Nameserver problems

fausett@radc.af.mil (Mark L. Fausett) (06/29/89)

HELP!
I have a name server which seems to be working properly, but doesn't
interface well with nslookup --

% nslookup
*** Can't find server name for address 127.0.0.1: No information
*** Default servers are not availible
%

other machines using a resolv.conf pointing at this machine get a similar
error.  BUT -- I can kludge the system by doing something like this:

% nslookup -l <some weird hostname here>

which eventually reports a timeout and connects to my local server!  while
this nslookup is working, other machines pointing at this machine can use
the server too!

WHAT IS GOING ON? PLEASE SOMEONE EXPLAIN THIS TO ME!

Mark Fausett
fausett@ra.radc.af.mil
fausett@tops20.radc.af.mil (this one's in the host tables)

steve@umiacs.umd.edu (10/06/89)

The domain name searching you're seeing was done deliberately, and is (for
most people) a feature rather than a bug.  People with sources generally
hack the resolver library sources to turn off the RES_DEFNAMES and/or
RES_SEARCH flags in the _res structure in res_init.c, then recompile...
but you probably can't do that.

The searching goes only up to two domains away from the root.  (For us,
that means that we'll look for 'foo' in foo.cs.umd.edu and foo.umd.edu,
but not foo.edu.)  The one case where this is legimately a problem is when
the second-level domain is served not by something local, but by (say) the
root servers.  Many of the military domains (i.e., navy.mil) are set up
this way.

I suppose it would be nice to have a way to turn off searching and default
names on a system-wide basis.  I'd still like to see the searching be made
a bit more flexible in the BIND resolver, but it seems unlikely (for
moderately good reasons) that such a change will never be put in by
Berkeley.

About MX sendmails: I think there is a fixed one out on uunet, probably as
sendmail.mx.  You might (if you don't mind losing the Sun sendmail YP
support) just choose to grab a copy of sendmail 5.61 from
ucbarpa.berkeley.edu instead, and use that over the Sun sendmail.

	-Steve

Spoken: Steve Miller    Domain: steve@umiacs.umd.edu    UUCP: uunet!mimsy!steve
Phone: +1-301-454-1808  USPS: UMIACS, Univ. of Maryland, College Park, MD 20742