Test your DNS using Dig, Nmap, Tcpdump Rumi, March 3, 2018March 3, 2018 For DNS resolution to succeed to 192.168.0.1, the DNS server at 192.168.0.1 will need to accept TCP and UDP traffic over port 53 from our server. A port scanner such as the nmap tool can be used to confirm if the DNS server is available on port 53 as shown… Continue Reading