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dnstop: Monitor BIND DNS Server Network Traffic From a Shell Prompt
dnstop is a great tool when maintaining a DNS server. Log file can give out required information but dnstop is just like top command for monitoring dns traffic. It is a small tool to listen on device or to parse the file savefile and collect and print statistics on the local network's DNS traffic. You can see information about all DNS clients, DNS queries and much more with this tool.