DNS issue

[hdeassis]

I have several users that intermitantly loose connection to our exchange 2003 server(our DNS server as well) and they can not open their Outlook anymore. The only way to fix this issue it to do a ipconfig /flushdns and registerdns command. When I ping the server with it's true domain name re: servername.local.lysdom I get an bad message saying "unknown host".

Please, do you have any ideas in why this could be happening and how to fix it?

Thx

H

 

[Jpoandl]

You need to add an A record to your DNS forward lookup zone.

servername.local.lysdom = and IP address

unless you are able to successfully ping this server by name, you will continue to run into this connectivity problem. As an alternative to fixing DNS, you can enter the servers IP address in the outlook profile instead of the FQDN. However, it would be better to fix DNS.

Also, make sure that your local domain clients are using the DNS server of the domain (and not the ISP router). Many times people use the router as a DHCP/DNS server. Because Active Directory requires DNS for communication, you should point all domain workstations and servers to use your Windows 2000/2003 DNS server.

-hope this helps..

Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please check out

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[hdeassis]

I've check all the above that you have mentioned and they are in place. The server does have a record DNS entry and all clients are pointing to the correct DNS servers.


Any other suggestions?

Thx

H

 

[Jpoandl]

Although, you seem pretty confident that this is all setup properly, I would guess that it is not.

Here is a good test. NSLOOKUP (run in dos or CMD window) is a utility that queries DNS. You can run this from the problematic client to see if the client can find the proper DNS server and A record.


When you run NSLOOKUP, you will see something like this:


c:\>nslookup
Default Server: dhcp64.srv.hcvlny.cv.net
Address: 167.206.3.151

Default Server: dhcp64.srv.hcvlny.cv.net = the DNS server that the client is pointing to. (This should be your internal DNS server)
Address: 167.206.3.151 (This is the IP address of the DNS server that the client is pointing to and using.

OK...so now type in the server name

> servera
Server: dhcp64.srv.hcvlny.cv.net
Address: 167.206.3.151

*** dhcp64.srv.hcvlny.cv.net can't find servera: Non-existent domain


----The above response shows that the A record for SERVERA does not exist. This is a problem.


Another test ----

>

http://www.yahoo.com

Server: dhcp64.srv.hcvlny.cv.net
Address: 167.206.3.151

Non-authoritative answer:
Name:

http://www.yahoo.akadns.net

Addresses: 216.109.118.66, 216.109.118.67, 216.109.118.70, 216.109.118.75
216.109.118.78, 216.109.117.108, 216.109.117.206, 216.109.118.64
Aliases:

http://www.yahoo.com

---This means that my DNS server knows that an A record for

http://WWW.yahoo.com

exists. = Successful response



You can type exit to leave the NSLOOKUP utility.


hope this helps..



Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please check out

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[Jpoandl]

Also check to see if your clients are using the proper DNS suffixes. DNS suffixes can be configured on each client in TCP/IP settings on the DNS tab.

This one must be included on your clients DNS Suffixes: servername.local.lysdom


-later

Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please check out

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[hdeassis]

Ok...I ran your test and the NSLOOKUP failed. However when I look for an record entry for our exch server wich also our DNS server I do find A record. Any other places I could check?

Thank for all your help.

 

[Jpoandl]

So, this means that your clients are not using your internal DNS server for resolution. DNS on the clients are not pointing correctly.

Just to be sure, do the NSLOOKUP test on the server itself. Maybe your DNS service is turned off?

For clients to use your internal DNS server, you must configure them to use your DNS server in TCP/IP (on the client) if you have only one DNS server, there should only be ONE entry....and the entry for DNS should be your internal DNS server's IP address.

Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please check out

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[hdeassis]

I've checked the svrcs and they are all running. Check the clients and they are pointing to our internal DNS servers. One think that I have notice is that under "Zone transfers", nothing is checked.

Henrique

 

[Jpoandl]

Was your DNS server able to use NSLOOKUP and successfully resolve the servers name?


Also, try to specify fully qualified domain name in your NSLOOKUP test. For example, instead of just typing SERVERNAME in NSLOOKUP...

type: servername.local.lysdom.com

If this resolves properly then review the following:

This one must be included on your clients DNS Suffixes: servername.local.lysdom



Also check to see if your clients are using the proper DNS suffixes. DNS suffixes can be configured on each client in TCP/IP settings on the DNS tab.

This one must be included on your clients DNS Suffixes: servername.local.lysdom


Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please check out

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[hdeassis]

No, I was not able to sucessfully resolve the server name by doing a NSLOOKUP.

 

[mlichstein]

Can you post an ipconfig /all from a client, as well as the server?

 

[hdeassis]

Sorry, but I'm no longer at the office. I can do this on Monday. Also I forgot to mention that we are also running WINS and I'm not sure if that could be causing a problem as well. Any thoughs?

 

[kjseever]

Has anyone found a solution to this problem? We are having the same issue here.

Thanks in advance.