topic Re: DNS resolution problem in Operating System - HP-UX

DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 07:37:25 GMT

Some info up front - We administer an HPUX 11.00 box in another state. We require them to inform us of any changes to their network. Recently they changed their DNS servers out and now we cannot get our server to resolve through their DNS. We get the following error message
*** Can't find server name for address x.x.x.14: Non-existent domain
*** Can't find server name for address x.x.x.46: Non-existent domain
*** Default servers are not available
We have actually looked at the ipconfig of these windows boxes and see no difference. Myself and the senior admin have looked at all of our config files and see nothing wrong. I am attaching resolv.conf and nsswitch.conf in a text file. If you all need any other info I will provide quickly. Thanks for all the help in advance.

Re: DNS resolution problem

RAC_1 — Mon, 30 Aug 2004 07:41:20 GMT

Can you access both the DNS servers you mentioned?? Can you ping/telnet to it??

The nsswitch.conf and resolv.conf both look OK.

Anil

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 07:43:08 GMT

I can ping both servers. They are windoze servers and they din't allow telnet into them.

Re: DNS resolution problem

harry d brown jr — Mon, 30 Aug 2004 07:48:17 GMT

Try this:

nslookup yourHPhostname x.x.x.14

This forces nslookup to use x.x.x.14 as a dns server. If you do not get a response or get an error message, then the issue is with the windoze boxes not allowing you to query. This is why people should NEVER use windoze boxes for DNS!

live free or die
harry

Re: DNS resolution problem

Geoff Wild — Mon, 30 Aug 2004 07:50:56 GMT

So, you can ping those DNS servers from the HP-UX 11.00 server?

Do you have a DNS server in your state?

Try this, from the HP-UX server:

nslookup
server server.yours.com

www.yourdomain.com

Does that work?

If yes, from a server or PC at your location, do the same - but to the new DNS servers.

Does that work?

"Can't find server name for address" usually indicates a connectivity issue - wrong subnet mask or something like that on those servers...but you can ping them from the HP-UX 11.0 server....

Rgds...Geoff

Re: DNS resolution problem

RAC_1 — Mon, 30 Aug 2004 07:51:16 GMT

Is the port that DNS uses open?? 53 - udp and tcp??

nsquery hosts "some_test_host_ip_address" "dns"

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 08:20:07 GMT

Ok. I did the nslookup myHPbox x.x.x.14 and it came back with an error like this Specified server is not available.
The configured name services and switch policy will be used.
Then I get the same messages I was getting.
I also did the nslookup from thei site using our dns and this worked. When I changed my pc to use theirs it came back failed. I think this is due to their firewall preventing me access to their dns.
I did the nsquery and it appears to work here is the output nsquery hosts www.yahoo.com dns

Using "dns" for the hosts policy.

Searching dns for www.yahoo.com
Hostname: www.yahoo.akadns.net
Aliases: www.yahoo.com
Address: 216.109.118.66 216.109.117.207 216.109.118.65 216.109.117.109 216.109.1
18.76 216.109.117.108 216.109.118.77 216.109.118.72
Switch configuration: Terminates Search
But if I just type in nslookup www.yahoo.com it gives me the same error messages. I am totally lost on this one. Is it working or not?

Re: DNS resolution problem

RAC_1 — Mon, 30 Aug 2004 08:26:03 GMT

Add serach keyworj to your resolv.conf

Like

domain xxx.com
search xxx.xom
dns server1
dns server2

Anil

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 08:45:32 GMT

Adding the search keyword didn't help. This is definitely annoying. I have the DNS search setup the same as mine except for domain and ip's. I am getting ready to give up since the server works for what they want anyway.

Re: DNS resolution problem

Geoff Wild — Mon, 30 Aug 2004 08:54:27 GMT

Out of curiosity, what is in the /etc/hosts file on the HPUX 11 server? In particular, the line for the host itself? is the FQDN there?

x.x.x.x hpserver hpserver.xxx.com

Rgds...Geoff

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 09:01:53 GMT

the host entry looks like this
x.x.x.x hpserver hpserver.

Re: DNS resolution problem

harry d brown jr — Mon, 30 Aug 2004 09:06:16 GMT

It should be
x.x.x.x hpserver hpserver.xxx.com

live free or die
harry

Re: DNS resolution problem

Geoff Wild — Mon, 30 Aug 2004 09:10:06 GMT

Ok, let's try forcing the hostname..

Set it to this in /etc/hosts:

x.x.x.x hpserver.xxx.com hpserver

In my nsswitch.conf:

hosts: files [NOTFOUND=CONTINUE] dns

In my resolv.conf:

domain mydomain.com
nameserver x.x.x.1
nameserver x.x.x.2
nameserver x.x.x.3
retrans 2500
retry 2

Rgds...Geoff

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 09:21:40 GMT

Thanks I'll try this during the next Oracle downtime. The "server name" is in the listener.ora file and I don't want to take any chances.

Re: DNS resolution problem

Geoff Wild — Mon, 30 Aug 2004 09:22:53 GMT

Just a thought, they (Windows Admins) added an A and a PTR record for your HP server?

Do you have dig installed on the HP Server?

Rgds...Geoff

Re: DNS resolution problem

Amiel Tutolo — Mon, 30 Aug 2004 09:25:42 GMT

I am not sure if they added anything for my server. Also what is dig?

Re: DNS resolution problem

Geoff Wild — Mon, 30 Aug 2004 09:36:01 GMT

dig - domain information groper

Note: nslookup is deprecated and may be removed from future releases.
Consider using the `dig' or `host' programs instead. Run nslookup with
the `-sil[ent]' option to prevent this message from appearing.

You get that when you install Bind 9.

If you just want dig, you can get it here:

http://hpux.ee.ualberta.ca/hppd/hpux/Networking/Admin/dig-2.0/

Rgds...Geoff

Re: DNS resolution problem

Bharat Katkar — Mon, 30 Aug 2004 09:36:59 GMT

Hi,
DIG:domain information groper

See the link below:
http://www.software.hp.com/portal/swdepot/displayProductInfo.do?productNumber=BIND812

Hope that helps.
Regards,

Re: DNS resolution problem

Bill Hassell — Mon, 30 Aug 2004 10:15:00 GMT

You wrote:

>> Ok. I did the nslookup myHPbox x.x.x.14 and it came back with an error like this Specified server is not available.

This is the key. The .14 DNS server is refusing to talk to your machine. It may be a DNS policy or a router issue. Until nslookup x.x.x.14 works, there is nothing you can do other than to hardcode all your needed IP addresses into /etc/hosts and use files then dns in your nsswitch.conf file. NOTE: your DNS administrator may be confusing WINS and DNS when they say they have gotten DNS working...WINS is useless on HP-UX.