Unable to BIND to destination server in DNS

[Jose Oliveira]

I'm still trying to figure out if someone out there has
seen this dreadful error message and how did you correct
it. I've looked all over the Internet for ways to fix this
error and I can't find one answer that will fix the
problem I'm facing. My SMTP server returns this error
message for every single message it tries to send.
We're using IIS 5.0, SP4 and all latest fixes from
Microsoft. ISA Server is correctly configured, it can
resolve names on behalf of all our users, all of our other
Internet services work perfectly, including our Exchange
server (which can send and receive e-mail behind ISA
Server). It seems as if the SMTP server (running alone on
a separate server) can't resolve it's DNS queryes, though
running NSLOOKUP proves it can.
Hope someone out there can help. I have called Microsoft
support, but..........
We have checked our DNS configuration several times and
found nothing wrong, but, if you have any ideas, we're
open to hear them.
Jose Oliveira.

 

[Kevin D. Goodknecht]

In

I'm still trying to figure out if someone out there has
seen this dreadful error message and how did you correct
it. I've looked all over the Internet for ways to fix this
error and I can't find one answer that will fix the
problem I'm facing. My SMTP server returns this error
message for every single message it tries to send.
We're using IIS 5.0, SP4 and all latest fixes from
Microsoft. ISA Server is correctly configured, it can
resolve names on behalf of all our users, all of our other
Internet services work perfectly, including our Exchange
server (which can send and receive e-mail behind ISA
Server). It seems as if the SMTP server (running alone on
a separate server) can't resolve it's DNS queryes, though
running NSLOOKUP proves it can.
Hope someone out there can help. I have called Microsoft
support, but..........
We have checked our DNS configuration several times and
found nothing wrong, but, if you have any ideas, we're
open to hear them.
Jose Oliveira.

Have you configured an external DNS server for it?

 

[Jose Oliveira]

-----Original Message-----
In Jose Oliveira <[email protected]> posted a question
Then Kevin replied below:

Have you configured an external DNS server for it?




.

Kevin, thanks for the reply.
Currently, I have the SMTP server's IP configuration
pointing to our ISA Server as the Gateway and 2 external
DNS servers on my ISP.
NSLOOKUP works just fine like that. I have tried to use
OUR 2 External DNS servers, it also did not work. I have
also tried to use our INTERNAL DNS server (which forwards
to my ISP's DNS servers) and it also did not work. The
funny thing is when using NSLOOKUP with any of our 3 DNS
servers (the 2 external or the internal) NSLOOKUP reports
an error and does not connect to our DNS servers. We're
about to take them down and try with a Linux box, or move
our DNS to the ISP, if the problem proves to be at DNS
level.
Regards and have a nice weekend.
Jose.

 

[Kevin D. Goodknecht]

In

Kevin, thanks for the reply.
Currently, I have the SMTP server's IP configuration
pointing to our ISA Server as the Gateway and 2 external
DNS servers on my ISP.
NSLOOKUP works just fine like that. I have tried to use
OUR 2 External DNS servers, it also did not work. I have
also tried to use our INTERNAL DNS server (which forwards
to my ISP's DNS servers) and it also did not work. The
funny thing is when using NSLOOKUP with any of our 3 DNS
servers (the 2 external or the internal) NSLOOKUP reports
an error and does not connect to our DNS servers. We're
about to take them down and try with a Linux box, or move
our DNS to the ISP, if the problem proves to be at DNS
level.
Regards and have a nice weekend.
Jose.

This sounds like it could be a configuration problem with ISA I don't use
ISA but it seems like someone posted a similar problem and it had something
to do with adding the machine to ISA DNS proxy user or something like that.

But now so far as the nslookup "error" if it is what I'm thinking of it is
asked several times a week here doe sit go something like this "can't find
server name for <ipaddress>"
That is nslookup performing a reverse lookup PTR for the IP of the server.
It does not mean DNS is not working, you can ignore it or configure a
reverse lookup.

If that is not the message please post the exact message, it is not really
an error.

 

[Jose Oliveira]

-----Original Message-----
In Jose Oliveira <[email protected]> posted a question
Then Kevin replied below:

This sounds like it could be a configuration problem with ISA I don't use
ISA but it seems like someone posted a similar problem and it had something
to do with adding the machine to ISA DNS proxy user or something like that.

But now so far as the nslookup "error" if it is what I'm thinking of it is
asked several times a week here doe sit go something like this "can't find
server name for <ipaddress>"
That is nslookup performing a reverse lookup PTR for the IP of the server.
It does not mean DNS is not working, you can ignore it or configure a
reverse lookup.

If that is not the message please post the exact message, it is not really
an error.





.

Hi Kevin,
Thanks for taking the time man, I really appreciate your
help.
The exact message from NSLOOKUP is this one:

c:\>nslookup
*** Can't find server name for address 10.10.0.1: Non-
existent domain
*** Can't find server name for address 10.10.0.9: Non-
existent domain
*** Default servers are not available
Default Server: UnKnown
Address: 10.10.0.1

It's funny as I'm pointing my computer to our 2 DNS
servers, using the internal network address, so there's
not even a firewall between them. Anyway, as you mentioned
in your previous reply, I'm capable of resolving names,
even with this error message.

I have been able to partly change the status of the
problem. I've changed the DNS server used by my SMTP
server to another ISP and now it seems the server is able
to resolve names, the message on the subject is not being
shown for all messages in the queue anymore. Now what I
get is a Connection dropped by the remote host and some
other messages return an error from the remote domain,
informing they can't resolve our domain (I believe it's a
reverse lookup). As I have found before on a Microsoft
article, it seems I have to reconfigure my DNS in
conjunction with my ISP because I'm on a subnneted zone.
Anyway, I'll keep researching this problem and I
appreciate if you have any additional comments.
Regards.
Jose Oliveira.

 

[Kevin D. Goodknecht]

In

Hi Kevin,
Thanks for taking the time man, I really appreciate your
help.
The exact message from NSLOOKUP is this one:

c:\>nslookup
*** Can't find server name for address 10.10.0.1: Non-
existent domain
*** Can't find server name for address 10.10.0.9: Non-
existent domain
*** Default servers are not available
Default Server: UnKnown
Address: 10.10.0.1

This is nslookup performing a reverse lookup on your DNS IPs.
It does not mean that DNS is not working, it only means DNS can't find the
reverse lookup zone and the PTR. DNS is reporting non-existent domain, so
DNS is working.
You can ignore it or configure a reverse lookup.
Does nslookup resolve any names after the initial start up?

 

[Ace Fekay [MVP]]

In

Hi Kevin,
Thanks for taking the time man, I really appreciate your
help.
The exact message from NSLOOKUP is this one:

c:\>nslookup
*** Can't find server name for address 10.10.0.1: Non-
existent domain
*** Can't find server name for address 10.10.0.9: Non-
existent domain
*** Default servers are not available
Default Server: UnKnown
Address: 10.10.0.1

As Kevin said, configure a reverse zone for your internal subnet and create
a PTR record for the DNS server and this message (it's a message, NOT an
error), will go away.

It's funny as I'm pointing my computer to our 2 DNS
servers, using the internal network address, so there's
not even a firewall between them. Anyway, as you mentioned
in your previous reply, I'm capable of resolving names,
even with this error message.

Not an error, but just a message as I stated.

I have been able to partly change the status of the
problem. I've changed the DNS server used by my SMTP
server to another ISP and now it seems the server is able
to resolve names, the message on the subject is not being
shown for all messages in the queue anymore.

What SMTP server are you using?
If Exchange, you need to only use the internal DNS. This is due to AD's
requirements.

Now what I
get is a Connection dropped by the remote host and some
other messages return an error from the remote domain,
informing they can't resolve our domain (I believe it's a
reverse lookup).

Yes it is. The recipient domains are using Reverse DNS.

As I have found before on a Microsoft
article, it seems I have to reconfigure my DNS in
conjunction with my ISP because I'm on a subnneted zone.

Yes, you'll have to contact them to create a PTR entry in their reverse zone
in their DNS for your SMTP server based on your domain name and not theirs.
This is assuming that your ISP's DNS is authorative for you domain name.
This is even if you are the SOA for your domain, since the IP block belongs
to them, unless of course, they delegate your specific public IP subnet to
your DNS server. Most may not do this.

Anyway, I'll keep researching this problem and I
appreciate if you have any additional comments.
Regards.
Jose Oliveira.

--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS IS" with no warranties.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory