topic Re: reverse lookup not working in Operating System - HP-UX

reverse lookup not working

hp_user_1 — Thu, 14 Aug 2008 18:20:10 GMT

Hello,

I have an rx3600 with 11.31 running. DNS is disabled. The settings are:

/etc/nsswitch.conf: hosts: files
/etc/hosts: 172.92.22.24 servera1

Problem is that I can ping the IP address, but not the hostname "servera1"...

Any ideas folks ???

Thanks

Re: reverse lookup not working

Steven E. Protter — Thu, 14 Aug 2008 18:27:51 GMT

Shalom,

Reverse lookup will not work with /etc/hosts support.

You need to install BIND 9 and configure a reverse look up server or configure it on an external DNS server.

http://h20392.www2.hp.com/portal/swdepot/displayProductInfo.do?productNumber=BIND

http://www.tech-faq.com/reverse-dns.shtml

http://support.microsoft.com/kb/245574

http://techrepublic.com.com/5208-23-0.html?forumID=102&threadID=253457&start=0

SEP

Re: reverse lookup not working

Patrick Wallek — Thu, 14 Aug 2008 18:34:16 GMT

That is not entirely accurate. If all you have is an /etc/hosts file then you should still be able to look up via name or IP address.

What happens when you do:

# nslookup servera1
Does this return the IP address?

# nslookup 172.92.22.24
Does this return the host name?

Re: reverse lookup not working

Tim Nelson — Thu, 14 Aug 2008 18:36:54 GMT

SEP U sure ?

ping should work both directions with only a host file..

Re: reverse lookup not working

Tim Nelson — Thu, 14 Aug 2008 18:39:08 GMT

Ignore my last post ( SEP has corrected ).

There is a new issue with nslookup when you have a DNS server that does NOT have its reverse configured correctly.

nslookup will fail but dig and nsquery work.

I may even have a post about this issue. One moment.....

Re: reverse lookup not working

Tim Nelson — Thu, 14 Aug 2008 18:41:18 GMT

Here was the issue I had..

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1170091

Re: reverse lookup not working

TTr — Thu, 14 Aug 2008 18:55:44 GMT

> Problem is that I can ping the IP address, but not the hostname "servera1"

Ping-ing the IP address does not tell anything about a name resolution problem.

Failing to ping the hostname is a direct (not reverse) name resolution issue.

Please answer Patrick's questions. It may be a hostname configuration issue or an /etc, /etc/hosts file permission issue or an invisible character in the /etc/hosts line. I assume you are doing this as root?

Re: reverse lookup not working

hp_user_1 — Thu, 14 Aug 2008 19:32:35 GMT

The DNS service is not running on the server.

nslookup works fine on both hostname and its IP address, and returns the right information. But ping only works on the IP address, and hangs on the hostname.

Re: reverse lookup not working

Bill Hassell — Thu, 14 Aug 2008 23:01:28 GMT

Run nsquery and post the results:

$ nsquery hosts 15.216.110.140

Using "files [NOTFOUND=continue UNAVAIL=continue] dns " for the hosts policy.

Searching /etc/hosts for 15.216.110.140
15.216.110.140 was NOTFOUND

Switch configuration: Allows fallback

Searching dns for 15.216.110.140
Hostname: hpqainspect.org
Aliases:
Address: 15.216.110.140
Switch configuration: Terminates Search