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Unable to flush dns entry

I am using toad for oracle development. Whenever i perform any operation in toad, it goes to an ip address to resolve the database server name. That IP address was previously used as our dns server but no more exists in our network. I flushed by dns using ipconfig /flushdns commad but unable to get ride of this IP address. Also I have reinstalled my oracle client and toad but that IP address is alwayes there.
Can any body suggest me some way to find out where this entry exist in windows DNS setting.


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Did you use NSLOOKUP?

In reply to: Unable to flush dns entry

Some client software caches that so use NSLOOKUP to determine if it's Windows or something else. Also check your HOSTS file.


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Yes I used nslookup

In reply to: Did you use NSLOOKUP?

I used nslookup to get info about that IP address but no domain exists against that IP address.


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Then we're done.

In reply to: Yes I used nslookup

Since your reply has only what you shared, we are done.

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Actual process

In reply to: Then we're done.

I used a network utility to find out the process which initiate call to that IP address and that is "system" process initiated by kernel32.dll.
On every operation in Toad, a new connection to that IP is initialized by this process.
I have no idea from where this process gets the IP Silly

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In reply to: Actual process

I can't continue without new clues. I noted NSLOOKUP to find out if the IP was being fetched from "Windows". If the lookup fails there then it's in your application.

But let's note another area people can't seem to communicate about. It's those cached items in the address toolbars such as Internet Explorer. Let's say I have an application that uses such a cached menu item. You might think it's remembering an IP when in fact it's just some menu pick that is in some buffer in the app's memory.

To figure out if it's Windows is a snap but your posts have so few words that I can't dismiss that yet.


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Whole Story...

In reply to: Sadly...

Let me tell you the complete story. We are using toad for oracle development on windows environment. From last 15 days, my Toad application response is very slow. Toad responds to the simple operations in minutes not seconds.
I ask my network guy to figure out the problem and we identified that on every operation, toad connects to an IP address to resolve the DB server names.
There was a dns server in our network with the IP mentioned above. Now this server no longer exists in our network. But whenever toad performs any operation, it always try to connect to that IP address.
I thought that it might be a problem at DB server end and I check with my colleagues, but no one is facing this problem.

I thought that may be some Toad related cache needs to be flushed or oracle client has some problem at its local cache. I reinstalled both applications but no avail.

I check windows' "hosts" file and there is no entry for that IP. Even i searched that IP address through text search in Windows folders but no text/config file have this entry.

I tried all what can i do but still that IP is there and my problem is also..........


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And still..

In reply to: Whole Story...

You didn't show it to be a Windows DNS issue. Your test with NSLOOKUP would have revealed this. And you are not sharing the results so no one can help. Here's an example result:
*** Can't find server name for address Non-existent domain
*** Default servers are not available
Default Server: UnKnown

Server: UnKnown

Non-authoritative answer:

If you have an invalid DNS in your Windows setup, then fix it and move on. But look over your posts. Not a word about the setup. I'm not there to see the screens.


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Message from nslookup

In reply to: And still..

Sorry for another small screen Happy

Message from nslookup against is

*** Can't find server name for address Non-existent domain

Today i searched my registry entries for above IP and no results. Even I reinstalled Windows networking services component.

Last question, How can i fix an invalid DNS setup.


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We can't.

In reply to: Message from nslookup

Let's see what you have told me about your DNS.... Nothing.

For NSLOOKUP to work for is what we call a REVERSE LOOKUP. Do you need a lookup or a reverse lookup?

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I Succeeded

In reply to: We can't.

Finally I succeeded to get ride of the IP. I manually clear all my application temp data and now Toad is running without any problem.

Thanks Bob, for all your replies and help Happy


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Good to read.

In reply to: I Succeeded

That's what I was thinking. It was not in Windows (easy to prove with nslookup) but in the app.


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