Nameserver

From Spamwiki

Nameservers give the IP addresses (there may be several, to rotate workload) for a domain name that is asked (queried).

Name servers or nameservers are hosts that contain records used to point a domain to a particular host. The domain name is said to be resolved to an Internet Protocol (IP) address.

There are other functions too, for example mail exchange addresses and reverse queries, but in our context this usually suffices.

An example query, full trace from the root servers:

Nameserver 192.33.4.12 (c.root-servers.net) tells that .eu domains can be found on these nameservers:

eu.                     172800  IN      NS      L.NIC.eu.
eu.                     172800  IN      NS      M.NIC.eu.
eu.                     172800  IN      NS      P.NIC.eu.
eu.                     172800  IN      NS      A.EU.DNS.BE.
eu.                     172800  IN      NS      B.EU.DNS.BE.
eu.                     172800  IN      NS      L.EU.DNS.BE.

Nameserver 195.66.241.178 (L.NIC.eu) tells that spamtrackers.eu domain can be found on these nameservers:

spamtrackers.eu.        86400   IN      NS      dns.ovh.net.
spamtrackers.eu.        86400   IN      NS      ns.ovh.net.

Nameserver 213.186.33.102 (dns.ovh.net) tells that www.spamtrackers.eu computer can be found:

www.spamtrackers.eu.    86400   IN      CNAME   spamtrackers.eu.
spamtrackers.eu.        86400   IN      A       213.186.33.19

So, www.spamtrackers.eu is actually spamtrackers.eu and has IP address 213.186.33.19

Understanding the concept of a nameserver is very important for reporting Internet abuse. One can then look up the nameserver owner and add the technical contact in a spam report. This nameserver recipient may be a downstream of a larger Internet Service Provider or reseller of web hosting.