I have a Cisco 877W running on my ADSL2+ service at home.
It is setup to act as a DNS server to answer DNS queries for my LAN and has the below commands as part of its configuration
ip dns server
ip dhcp pool LAN
network 192.168.2.0 255.255.255.0
My question is, when I scan my WAN IP for open ports, port 53 (DNS) is open. Does this mean my router will be acting as a DNS server for anyone on the internet who directs DNS queries to my WAN IP?
If so, am I able to turn off port 53 towards the Internet, or do I need to add an an access-list to only accept queries from my internal network.
Thanks for your feedback.