DNS unable to resolve

G

Guest

Good Day, I have the weirdest problem that I really need assistance on. I
have several programs that run across our WAN from one of our remote sites
and everday, users have to repair their network connection before they can
log into these applications or connect to the intranet that is hosted in the
same location. Even at this location they have to do the same. What I have
tried is adding the DNS entry for that particular server/s into my LMHOST
file, I have tried creating a new DNS server, but have been completely
unsuccessful. We have figured out that on the repair process, it is the
ipconfig /registerdns command that actually fixes the problem. Does anyone
have any suggestions? Thank you

Scott
 
H

Herb Martin

Scott Keegan said:
Good Day, I have the weirdest problem that I really need assistance on. I
have several programs that run across our WAN from one of our remote sites
and everday, users have to repair their network connection before they can
log into these applications or connect to the intranet that is hosted in the
same location. Even at this location they have to do the same.

Do you mean the client side "repair Network"?

That is fine for a user, but you probably should not be
using it -- except for a quick emergency repair.

If you avoid that and track down the actual cause you
might be able to isolate and fix it permanently.
What I have
tried is adding the DNS entry for that particular server/s into my LMHOST
file,

What are you expecting that to accomplish?

A DNS server is referenced by it's IP address
in it's NIC properties. Name resolution is NOT
an issue for the DNS server itself (as a DNS server.*)

*The DNS servers may need to be resolved by both DNS
and NetBIOS for OTHER purposes on that same server
machine however.
I have tried creating a new DNS server, but have been completely
unsuccessful.

You mean you cannot even add DNS server to your
server machine(s)? Completely unsuccessful?

We have figured out that on the repair process, it is the
ipconfig /registerdns command that actually fixes the problem. Does anyone
have any suggestions? Thank you

Yes, it sounds like you are losing dynamic entries which
makes it likely you have enabled SCAVENGING with
a ridiculously short scavenging period, norefreshinternal,
and refreshinternal.

These (IF enabled) should be set to weeks, not days.

Check your DNS server and zone properties for scavenging
settings -- set the periods VERY LONG.

Another (less likely possibility since it repairs so easily) is
that your clients are NOT set to use strictly your own DNS
servers but are set to some combination which includes
other (external) DNS servers for something, such as the ISP
or some Internet resolving DNS server.
 
G

Guest

Do you mean the client side "repair Network"?
We are doing repairs from the client side because that is the only way that
we can get them talking back to the Intranet server and applications
If you avoid that and track down the actual cause you
might be able to isolate and fix it permanently.
I have tried to find the actual cause but have exhausted all possibilities
You mean you cannot even add DNS server to your
server machine(s)? Completely unsuccessful?

No, I simply meant that creating a new DNS and routing clients to it instead
of the possible bad DNS server was unsuccessful in that that was not the
solution

We haven't made any adjustments to the DNS server in lines of scaveging.
Another (less likely possibility since it repairs so easily) is
that your clients are NOT set to use strictly your own DNS
servers but are set to some combination which includes
other (external) DNS servers for something, such as the ISP
or some Internet resolving DNS server.
Could this create an issue. They have always been set to use multiple DNS
servers which are legit. The odd thing is that when they do the repair, they
are fine all day but when turn off and come in in the morning, they are back
with the same problem. Moreover, this is a hit and miss issue, sometimes it
happens on a certain machine and the next day, it might be ok and someone
else has that problem.

Also, our DNS server is a Netware 5.1 box. I will check it out on the
scaveging and see if there is anything strange there. Thanks
 
H

Herb Martin

Scott Keegan said:
We are doing repairs from the client side because that is the only way that
we can get them talking back to the Intranet server and applications

That wasn't really the focus of my question so perhaps
I should have been more specific: my real question
was to ask if you were using that auto-repair feature.
I have tried to find the actual cause but have exhausted all possibilities

You have actually discovered (explained later by you)
that "registerDNS" fixes the problem, so you didn't
really exhaust the possibilities.

That was the key to my suggestion: Getting away from
the automatic repair.
No, I simply meant that creating a new DNS and routing clients to it instead
of the possible bad DNS server was unsuccessful in that that was not the
solution

What happened then?
We haven't made any adjustments to the DNS server in lines of scaveging.

Could this create an issue. They have always been set to use multiple DNS
servers which are legit.

Clients must NOT be set to multiple DNS servers that
return DIFFERENT answers.

Whenever such "seems" to work, it is a mere accident,
and it unpredicatably unreliable.
The odd thing is that when they do the repair, they
are fine all day but when turn off and come in in the morning, they are back
with the same problem.

That is consistent with scavening (on the server) or
with clients set to multiple "sets of" DNS servers.

All internal clients must be set SOLELY to the Internal
DNS server (set).

If you need to resolve additional names (not held in zones
on the internal server set) then you must arrange for the
internal DNS servers to do that (forwarding, 'cross secondaries',
etc.)
Moreover, this is a hit and miss issue, sometimes it
happens on a certain machine and the next day, it might be ok and someone
else has that problem.

Those are the symptoms of setting a mixture of DNS server
"sets" -- trying to have the clients resolve internal and external
names DIRECTLY on their own -- rather than arranging their
internal DNS server (sets) to do that.
Also, our DNS server is a Netware 5.1 box. I will check it out on the
scaveging and see if there is anything strange there. Thanks

Well, you might have mentioned that as scavenging is
usually a Windows Server DNS issue (it's off by default
but easy for the unwary admin to enable badly.)

I know almost nothing of the Netware server but find that
trying to use such DNS servers with a Windows network
is usually like "swimming upstream" -- i.e., possible but
a LOT OF WORK.

However, that server SHOULD work -- and the problem
is likely those incorrect settings on the client NIC -> IP
properties.
 
G

Guest

Thanks, I will remove the other DNS entry and use a singular one and see. I
will likely know better tomorrow, because this only seems to happen when they
atart their machines in the morning.

Also, you asked what happened when they connected to the new Windows 2003
DNS server. The result was the same that they could not contact the intranet
or applications until they right click on their local area connection and
select repair.

However, with the new DNS server, I still had 2 entries in the DNS section
for their IP and my server was setup not to forward requests.
 
H

Herb Martin

Scott Keegan said:
Thanks, I will remove the other DNS entry and use a singular one and see. I
will likely know better tomorrow, because this only seems to happen when they
atart their machines in the morning.

Also, you asked what happened when they connected to the new Windows 2003
DNS server. The result was the same that they could not contact the intranet
or applications until they right click on their local area connection and
select repair.

Ok, that is different than "completely unsuccessful"
and TENDS to implicate the clients which we suspect
for other reasons.
However, with the new DNS server, I still had 2 entries in the DNS section
for their IP and my server was setup not to forward requests.

Right -- chance are you would not have been likely
to create the new server with the exact same problem
(e.g., low scavenging settings)

The Client NIC DNS NEEDS fixing, even if you have
other problems that we must later help you find.

Are you set for resolving the Internet (or other zones/domains)?

Usually your internal DNS servers will FORWARD to the
ISP or your Firewall/DMZ caching only DNS server if you
have one of those.
 
H

Herb Martin

then the DNS forwards requests to the ISP's DNS for resolution. We have
tested here removing the external DNS entry and it seems that our DNS is not
resolving outside. We just discovered this.

This is the reason I indicated (before) that you
should have your INTERNAL DNS forward to
some DNS that resolves the Internet for them.
 

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