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mx record lookup, domain mx records

Main content page - mx record lookup.IP is the usual abbreviation for Internet Protocol. It is also a common abbreviation for different things in different fields.
The host name contained in an MX record must have an address, i.e. an A or AAAA DNS record. CNAME aliases are prohibited in an MX record data, while CNAME is allowed for the MX record label, that is for the domain name leading to the MX record itself.
(Immediate parallelism might not be optimal, at least without information-sharing between the lookup threads, as that would probably lead to duplicate non-cached delegation chain lookups.) An additional concern is the address selection, which may, in some circumstances, prefer AAAA records over A records even when the node does not have any IPv6 connectivity [WIP-RDP2004].
An MX record or Mail exchanger record is a type of resource record in the Domain Name System (DNS) specifying how Internet e-mail should be routed using the Simple Mail Transfer Protocol (SMTP). Each MX record contains a preference and a host name, so that the collection of MX records for a given domain name point to the servers that should receive e-mail for that domain, and their priority relative to each other.
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