DNS server can be attacked using various techniques such as [a] DNS spoofing [b] Cache poisoning [c] Registration hijacking One of the simplest ways to defend is limit zone transfers between nameservers by defining ACL. I see many admin allows BIND to transfer zones in bulk outside their network or organization. There is no need […]


You can use a tool called named- checkconf to check BIND dns server (named daemon) configuration file syntax under Linux / UNIX. It checks the syntax, but not the semantics, of a named configuration file i.e. it can check for syntax errors or typographical errors but cannot check for wrong MX / A address assigned […]


The domain name service provided by BIND (named) software. It uses both UDP and TCP protocol and listen on port 53. DNS queries less than 512 bytes are transferred using UDP protocol and large queries are handled by TCP protocol such as zone transfer. i) named/bind server – TCP/UDP port 53 ii)Client (browser, dig etc) […]


BIND is the Berkeley Internet Name Domain, DNS server. It is wildly used on UNIX and Linux like oses. You can use following tools to troubleshoot bind related problems under UNIX or Linux oses. Task: Port 53 open and listing requests By default BIND listen DNS queries on port 53. So make sure port 53 […]