Re: DNS Problem

On Mon, 31 Mar 2003 18:33:36 +0200, dsun wrote:

> See below for answers to your questions.
> 
> On 31 Mar 2003 at 9:40, Pete Peterson wrote:
> 
> 
>> > From: [email protected]
>> > To: [email protected]
>> > Subject: DNS Problem
>> > 
>> > I have a RedHat 7.0 system acting as my Internet gateway for my LAN. 
>> > I connect using an ISDN line.  I own a domain
>> > www.davidsconsultants.com.  I recently changed hosting services.  I am
>> > now running into the following problem.
>> > 
>> > If I connect to my ISP using a Windows 2000 machine and ping the
>> > address www.davidsconsultants.com I get the correct IP address as
>> > registered in the DNS.  When I connect using the Linux box the
>> > ifup-post script was over writing my resolv.conf file with the wrong
>> > DNS servers.  I took out the part of the script that overwrites the
>> > resolv.conf file.  Now when I test the DNS resolution using host
>> > www.davidsconsultants.com I get the correct information.
>> >  However, I am still unable to connect to the new host using Netscape.
>> >   Nor
>> > can I retrieve my mail.
>> 
>> You need to explain your configuration better.
>> 
>> You say the Red Hat machine is a gateway.  Is the connection from the
>> win2k machine passing through that gateway, or are you connecting one
>> and disconnecting the other for the two experiments you mention?
> In general the Win2k machine accesses the Internet through the Linux
> gateway. As a backup I am also able to connect directly from the Win2k
> machine.  In one scenario the Linux machine connects to the internet but
> access to www.davidsconsultants.com either from the Linux machine or from
> the Win2k machine goes to the wrong IP address.  In the other scenario,
> the Linux machine is disconnected from the Internet, the Win2k machine
> connects directly to the Internet and accessing www.davidsconsultants.com
> goes to the correct IP address.
> 
> 
>> Does the win2k box connect to the outside through the gateway OK.
> Yes.  I am able to access other sites without a problem.
> 
> 
>> Do you have a firewall set up on the Red Hat machine or any other
>> firewall/router box?
> I have a firewall setup on the RedHat machine.
> 
> 
>> What do you mean by "the wrong DNS server"?  If you're making a DHCP
>> connection to your ISP, the resolv.conf should be pointing to the ISP's
>> DNS servers.
> On the Win2k machine I specify my DNS servers (primary and secondary) as
> 192.115.106.10, 192.115.106.11 as per instructions from my ISP.  I edited
> the resolv.conf file to reflect this as well.  However, when I was
> connecting on the Linux machine the resolve.conf file was being
> overwritten with 192.115.106.35, 192.1115.106.10.  When I query the
> 192.115.106.35 DNS server for www.davidsconsultants.com I get the wrong IP
> address (66.216.18.92).  When I query the 192.115.106.10 DNS server for
> www.davidsconsultants.com I get the correct IP address (203.194.198.198).

Interestingly, I get 66.216.18.92 if I query 192.115.106.11.  Was that
address associated with your previous service?  Perhaps you're
getting some old DNS records that haven't expired?  Is your "ISP" the same
as your "hosting service"?  Is 203.194.198.198 a static IP assigned to
you?  If so, are you still setting up the port with DHCP or did you 
configure it as a static address?  

I assume 192.1115.106.10 was a typo (did you mean 192.115.106.10?).

It appears to me that it's not your machine that's messed up, but
rather something external to you in the DNS records.  Can you elaborate
on ISP/DNS/(static or dynamic)?


 
> I tried to take out the part of the script that was overwriting the
> resolv.conf file.  This helped in the sense that when I tried to ping
> www.davidsconsultants.com I got back the correct address.  However, when I
> went to Netscape I was not directed to the correct server (i.e. pages that
> I had added to the new host did not come up but did when I accessed them
> via IP address).

You shouldn't have to do that.  It's a symptom of something else
broken.  


>> Are you maintaining the DNS for davidsconsultants.com?  I see the
>> nameservers are ns{1,2}.station192.com.  Note that the MX record is
>> referencing a CNAME.  That's not legal, the MX should point to an A
>> record.  You should either make the MX point to 'davidsconsultants.com'
>> or add an A-record for mail.davidsconsultants.com.  Note that violating
>> this constraint usually causes no problems, but you might as well do it
>> right.
> I am not maintaining it.  I will pass this along to support at the hosting
> service.
> 
> 
>> 
>> What if anything do you have set up for firewalls?
> I am using IP Masquerade and IP Chains
> 
> 
>> > Can anyone explain to me why even though host is returning the correct
>> > information Netscape is not going to the correct site?
>> 
>> I can make both POP and HTTP connections (but not imap3) to
>> davidsconsultants.com.  If you supply more details, somebody should be
>> able to help you figure out what's not working for you..
> 
> I hope this gives you enough information to help me out.
> 
> Thanks,