How can I find the origins of conflicting DNS records?
You'll want the SOA (Start of Authority) record for a given domain name, and this is how you accomplish it using the universally available nslookup command line tool:
command line> nslookup
> set querytype=soa
> stackoverflow.com
Server: 217.30.180.230
Address: 217.30.180.230#53
Non-authoritative answer:
stackoverflow.com
origin = ns51.domaincontrol.com # ("primary name server" on Windows)
mail addr = dns.jomax.net # ("responsible mail addr" on Windows)
serial = 2008041300
refresh = 28800
retry = 7200
expire = 604800
minimum = 86400
Authoritative answers can be found from:
stackoverflow.com nameserver = ns52.domaincontrol.com.
stackoverflow.com nameserver = ns51.domaincontrol.com.
The origin (or primary name server on Windows) line tells you that ns51.domaincontrol is the main name server for stackoverflow.com.
At the end of output all authoritative servers, including backup servers for the given domain, are listed.