Block end users changing DNS Settings on Cisco Router

[dpoulter1]

• I'd like to know if it is possible to block end users from changing DNS settings on their local device. We are using a DNS based filtering service and need the DNS addresses to stay the same. Can this be done with an ACL?

1. We are running a server which runs DNS, for examples sake let's say it's 10.10.10
2. i want to block vlan 30 from chaining the DNS addresses which is an address of 10.10.30.0/24.

any help would be greatly appreciated

thanks

Dan

[Mark Malone]

It should be done at the IT level who manage the desktops/laptops etc , they should be able to role out policy to prevent users accessing there TCP/IP settings and changing DNS settings

If you know what there using as the other DNS like 8.8.8.8 you could block it by port number to the LAN but usually its done on IT level as if you block 1 they will use another and you will be updating acls constantly, yiou could try block all and just allow yours through not sure if that will work though , we lock it down at pc level