Search for mail exchanger (MX) records using dig
Contributed by Rex 
Tagged: BIND and DNS Mail exchanger or MX records in DNS are used to route email for a domain. The dig utility makes it easy to search for this type of DNS record.
To search for the MX records for the domain tech-recipes.com, use:
dig mx tech-recipes.com
This will query the DNS server configured in your operating system. Often times it is useful to query against a different DNS server. To perform the same query above against the name server ns3.notarealdomain.com:
dig @ns3.notarealdomain.com mx tech-recipes.com
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