User's DNS or router's DNS... which one rules?

[steveandon]

Hello all
I am trying to figure out which DNS settings take precedence on a DHCP network: the user's or the router's?

For example, let's say my router is set to provide DHCP, and of course in the router firmware I tell it the static addresses of my DNS.

If a user then connects to the network, and they have specifically defined a DNS in their TCP settings, does the router ignore that and use its own settings, or does the user's setting override?

Or does it depend on the type of router and the firmware design?

thanks for all replies!

 

[Wishdiak]

steveandon,

The options that are specified by the DHCP server are only used by the client computer if the client is set to automatically obtain these options (DNS servers, default gateway, etc.)

If the client computer has hardcoded DNS servers, then these will be used rather than the DNS servers provided by the DHCP server.

The client computer can still get an IP address lease through DHCP and not use the other DHCP options provided by the DHCP server.

Wishdiak

http://www.wishdiak.com

 

[steveandon]

thanks for the reply wishdiak! however i think this might be router specific... i just talked to linksys tech support and they say the opposite, they say that if a client has hardcoded their DNS settings, then they will not be able to access the internet if the router has a different setting. they say the client MUST change their setting to "obtain DNS automatically" if the router has a hardcoded DNS. any further thoughts?

 

[Wishdiak]

steveandon,

It might be router specific. Is that an older Linksys from before the Cisco buyout?

Let's get specific with your problem. What model Linksys router do you have, what client OS, and do you have any bridges/hubs/switches between the client and the router?

Ideally, your router should pass all traffic intended for a host on another network segment (such as DNS traffic) through the router without checking it's DNS entries.

Wishdiak

http://www.wishdiak.com

 

[dearingkr]

Wishdiak is correct in his first reply.

If you have hard-coded DNS settings in the PC, then the PC will use that, doesn't matter what kind of device is supplying DHCP.


MCSE CCNA CCDA

 

[ricpinto]

steveandon,

dearingkr and Linksys Tech Support are both right. The reason the you can't go to internet is that the hardcoded DNS setting is not working(big possibility).

Assuming ping ports are open.

Do this test and post the results.

1. ping

http://www.yahoo.com

2. ping 66.94.230.44