DNS/Intranet Help

[Salman]

Hello,

I have intranet running on my netwok. The problem is that
when the internet goes down, my intranet doesnt work
either. Everything is connected to the same LAN but still
when the internet going down my DNS server doesnt respond
to the intranet request that it gets from the
workstantion.

Do you know if there is some setting that i need to add o
change to make my DNS to reslove to the incoming request
on the intranet even when the internet is not working.

Thank you.

DNS/Intranet Help

 

[Lanwench [MVP - Exchange]]

Running AD? Make sure alll servers and workstations specify *only* the
internal AD-integrated DNS server's IP address in their network settings.
The AD-integrated DNS server should be set up with forwarders to your ISP's
DNS servers for external resolution. See
http://support.microsoft.com/default.aspx?scid=kb;en-us;300202 for more
info.

 

[salman]

Yes i am running AD and all my workstations are pointing
to my internal DNS servers.

I dont have any forwarders setup right now and the
internet still works. I am not sure how our clients are
connecting to the internet without the DNS forwareders?

I looked at the DNS Cache and it has all the external
websites that are visited listed, but i dont understand
how we can connecting to them?

 

[Lanwench [MVP - Exchange]]

Yes i am running AD and all my workstations are pointing
to my internal DNS servers.

I dont have any forwarders setup right now and the
internet still works. I am not sure how our clients are
connecting to the internet without the DNS forwareders?

Root hints - but I'd use your ISP's DNS servers. It's faster.

 

[Salman]

Should i remove all root hints and then add forwards???
I am not sure what root hints do?
If i do a tracert on www.yahoo.com, it goes straight to
my gateway's ip address and then goes out to the
internet. It doesnt even go through my DNS servers? How
can i make all internet and Intranet request to go
through my DNS server first and if it does reslove then
forward it to my ISP's DNS server.

Salman

 

[Lanwench [MVP - Exchange]]

Should i remove all root hints and then add forwards???

No need to remove the root hints. Just add the forwarder.

I am not sure what root hints do?

See if http://support.microsoft.com/?scid=kb;en-us;300202 helps...

If i do a tracert on www.yahoo.com, it goes straight to
my gateway's ip address and then goes out to the
internet. It doesnt even go through my DNS servers?

No, it first looks it up via DNS for resolution. The *traffic* goes out
through your default gateway.

How
can i make all internet and Intranet request to go
through my DNS server first and if it does reslove then
forward it to my ISP's DNS server.

That's what the forwarder is for. If all computers & servers point to your
AD DNS server, they will first look internally, and if they don't find it
there, they'll use the forwarder & try to resolve via that DNS server.

 

[Kevin D. Goodknecht Sr. [MVP]]

In

Should i remove all root hints and then add forwards???
I am not sure what root hints do?
If i do a tracert on www.yahoo.com, it goes straight to
my gateway's ip address and then goes out to the
internet. It doesnt even go through my DNS servers? How
can i make all internet and Intranet request to go
through my DNS server first and if it does reslove then
forward it to my ISP's DNS server.

Leave the Root Hints, the root hints are servers on the internet that know
where the Top level Domain DNS servers are. If your ISP's DNS becomes
overloaded or if you don't have forwarders enabled you DNS will get a
referral from the Root Hint servers to the TLD servers where it will be able
to find the second level domain name your looking for. IOW, for example.com
the root will send you to the com gTLD servers, which should know where the
example.com content DNS servers are.

That being said, DNS does not take part in routing, DNS only delivers the IP
address to the client. The routing software does the rest. and that's what
tracert shows.
All you need to do is put your DNS server in your client settings. The fact
the when you tracert www.yahoo.com and it goes to the IP address of
www.yahoo.com tells you that DNS is doing its job, if it wasn't, you'd get
host unknown.

 

[Salman]

O.K now i understand how DNS and Root hints work. Thank
you for your help. But there is still one more thing that
i dont understand.

If i dont have fowarders already setup how can i connect
to the internet and should all intranet request be
processed anyways?

Salman

 

[Lanwench [MVP - Exchange]]

O.K now i understand how DNS and Root hints work. Thank
you for your help. But there is still one more thing that
i dont understand.

If i dont have fowarders already setup how can i connect
to the internet

Connect, or resolve Internet domain names? For the former, well, it's your
default gateway/router. For the latter, root hints are doing their job. Just
set up the forwarders and be done with it.

and should all intranet request be
processed anyways?

Yes, if everyone's pointing at the AD DNS IP only, and no external/ISP DNS
servers are listed in their IP configs (for servers and workstations alike).