It is possible that your router is blocking traffic to those DNS servers. You provided some helpful information but not enough for us to find the problem yet.
One of the possible issues could be an issue with routing on the router to outside destinations, or it could be an issue with the way that NAT is configured, or it could be that there is an access list on one of the interfaces of the router. Or it might be possibly an issue with the configuration of the default gateway on the PCs on your inside connection.
A good place to start is with the question of whether you can access resources in the Internet by IP address if you can not get to the DNS server to resolve the name? For example the IP address of www.cisco.com is 184.108.40.206. If you put that address into your browser do you get to cisco.com?
It would also be helpful if you would post the configuration of your router.
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interface we use the VLAN tag to demultiplex the VLANs. The switch needs
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decision. To do this we require the switch to do...
[toc:faq]Introduction:Netdr is a tool available on a RSP720, Sup720 or
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IntroductionOSPF, being a link-state protocol, allows for every router
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