DNS servers to be used

[Christoph Kling]

Hello,

I am running a Windows XP SP3 computer with several network adapters. To
configure the order in which the settings of these adapters are used, I
changed the priority in the adapters and bindings tab (system control /
networking / advanced / advanced settings). After that nslookup uses the
correct DNS servers of the network adapter with the highest priority, but
windows itself does not. When I ping a host using its name, a dns server of
an adapter with a lower priority is being asked (I used a sniffer to find
that out). iptables /flushdns and a reboot does not help. Has anybody an
idea, what the reason for that behaviour could be? Do I need to change
something else to make windows use the dns servers of the adapter with the
highest priority? Thank you!


Regards

Christoph Kling

 

[Anteaus]

I'm reasonably sure that DNS settings (for multiple fixed-IP adaptors,
anyway) are not adaptor-specific. Thus you can't do this directly. A netsh
script, launched on change of adaptor, might be an option.

 

[Christoph Kling]

Hi Anteaus,

thank you for your reply. If I type ipconfig /all, I can see DNS settings
for each adapter. I don't want Windows to take different dns settings for
different connections. I want Windows to use the DNS servers of a a certain
adapter - always. I don't want windows to use the DNS servers of other
connections. How can I archieve this?


Regards

Christoph Kling

 

[Jack-MVP]

HI
There is No DNS server on adapters. DNS is a general Network Server that the
computers use it to resolve Network or Internet addresses..
The DNS number that is configured in the TCP/IP setting tell the adapter the
address of the DNS server.
On one cohesive Network the DNS address in all Network adapters is usually
the same.
On home Network without a Router the DNS server is over the Internet
provided by the ISP.
If there is a Router it provides a local DNS server.
If you have a Router the DNS setting of the adapters can be set to Auto
Obtain and it would use automatically the Router's DNS.
If you want to configure the DNS address manually you have to type the
Router's core IP as the DNS Server on each computer's Network card.
Maybe this can Help, http://www.ezlan.net/debug.html
Jack (MS, MVP-Networking).

 

[Christoph Kling]

Hi Jack,

thank you for your reply. To be more specific, here is the concrete problem:

I have a wireless card in my computer and it obtains the dns settings from
the dhcp server. The dhcp server tells my wireless adapter to use the router
as dns server.

Next, I have a tap virtual network device, which is being used by openvpn to
establish a vpn connection to a remote network. It is being displayed as a
normal network adapter, just like for example the device that is created if
you install a cisco vpn client. This virtual adapter receives its dns
settings from another dhcp server (the one within the network which I
connect to via vpn).

If I am connected to the vpn network (over the wireless connection), windows
has two different dns settings with two different dns servers available.
Which I want is, that windows uses the dns settings of the wireless adapter
when I am not connected to the vpn and when I am connected to the vpn, it
should use the dns settings of the vpn adapter.

This should be possible by giving the vpn adapter a higher priority in
system control / networking / advanced / advanced settings. But it does not
work. Whether I am connected to the vpn or not, windows uses the wireless
dns settings.

Hopefully, I could explain my problem a bit more detailed.


Regards

Christoph Kling

 

[Ryan Rule]

Christoph, I occasionally have the same problem with my VPN connections.
I also have this problem when using wired and wireless at the same time
(both DHCP).

I do like the response "There is No DNS server on adapters" the obvious lack
of understanding of *Windows* is funny although extremely inaccurate and
unhelpful.

Anyway, I haven't had the chance to try the following and I don't know if it
is different than the bindings tab that you already found, but I believe that
MS is claiming to address your specific situation here (regarding VPNs):

http://support.microsoft.com/kb/311218

Good luck,
Ryan