I asked in this list the following 2 questions:
1. How to make sure that all nameserver lookups will consult the
/etc/hosts file first, and
2. Why only the first server listed in /etc/resolv.conf file is
contacted for nameserver lookups.
I received 4 replies. My sincere thanks to:
Mike Iglesias <iglesias_at_draco.acs.uci.edu>
"John F. Marten" <root_at_tigger.oslc.org>
wmills_at_WellsFargo.COM
Gary Gladney <gladney_at_stsci.edu>
Mike answered question #2:
That is the way it works. The first nameserver is consulted, and
if it is not available, the others are tried in the order given in
/etc/resolv.conf. If the first nameserver cannot properly resolve
names, it should not be used.
For question #1:
John wrote:
i'm not sure DU looks at /etc/hosts anymore although i keep mine
around just in case ;>) . anyway make sure your hosts/servers are
listed in the /etc/namedb/hosts.db file.
Gary wrote:
You have the setup right. If you are using nslookup to check,
you will notice that nslookup only uses DNS. It's a DNS tool,
don't mean to sound ignorant. Try using telnet instead and
change the address of a host in your hosts file and see if it
still works.
wmills wrote:
Is it possible that your hosts file is somehow corrupt? That
would be my first guess.
Gsry's answer hit it on the nail. Nameserver lookups use DNS and
hence _will_ go to a nameserver. But, telnet, ping, et al will
happily consult the /etc/hosts file first.
What was my problem? I have several short-form names in /etc/hosts
file for the hosts that are not listed in the DNS tables. These
names should be separated by spaces and not commas as I had.
###.###.###.### host.domain host1,host2,host3
is INcorrect.
###.###.###.### host.domain host1 host2 host3
is correct and it works.
Cheers and thanks to the four kind persons who answered my query.
-- mahendra
.........................................................................
A. Mahendra Rajah Email: Mahendra_at_Meena.CC.URegina.CA
VMS & DUNIX Systems Manager Phone: (306) 585-4496
Dept. of Computing Services FAX: (306) 585-5060
University of Regina,
Regina, Sask., S4S 0A2
Canada.
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Received on Wed Jun 02 1999 - 19:41:18 NZST