mx record การใช้

• "RDATA " is data of type-specific relevance, such as the IP address for address records, or the priority and hostname for MX records.
• Regardless of how one interprets the RFCs there is an advantage to choosing to deliver to higher numbered MX records when receiving a 4xx error from a primary mail server.
• The Domain Name System ( DNS ) associates a mail server to a domain with an MX record containing the domain name of the host ( s ) providing MTA services.
• The SMTP RFC is ambiguous about exactly what kinds of delivery failure must result in re-attempting delivery via more distant MX records ( those with higher preference values ).
• But when the sender retries later, the RFC is silent about whether the sender should retry the same server that gave the previous temporary error or a more distant MX record.
• Each domain name on the internet has a series of one or more MX records specifying mail servers responsible for accepting email messages on behalf of that domain, each with a preference.
• When an e-mail message is sent through the Internet, the sending mail transfer agent ( MTA ) queries the Domain Name System for MX records of each recipient's domain name.
• Alternatively, sometimes spammers only target the lowest-distance MX records for domains, and do not fall back to higher-distance MX records when the lowest-distance MX records are unreachable.
• Alternatively, sometimes spammers only target the lowest-distance MX records for domains, and do not fall back to higher-distance MX records when the lowest-distance MX records are unreachable.
• Alternatively, sometimes spammers only target the lowest-distance MX records for domains, and do not fall back to higher-distance MX records when the lowest-distance MX records are unreachable.
• Sending servers that retry the higher MX records will be able to deliver their outgoing mail immediately, while servers like qmail will be delayed typically for an hour till the primary server allows it.
• Other methods for establishing a relation between an IP address and a domain in email are the Sender Policy Framework ( SPF ) ( which itself relies on reverse DNS ) and the MX record.
• It is not specific about what should cause the sender to use a higher-preference MX record, merely that the sender must be " able " to use higher-preference MX records.
• It is not specific about what should cause the sender to use a higher-preference MX record, merely that the sender must be " able " to use higher-preference MX records.
• Some servers ( such as Sendmail and Postfix 2.0 or earlier ) will only use more distant MX records if the servers specified in the shortest-distance MX records could not be contacted at all.
• Some servers ( such as Sendmail and Postfix 2.0 or earlier ) will only use more distant MX records if the servers specified in the shortest-distance MX records could not be contacted at all.
• In order for greylisting to work in such cases, all backup mail servers ( as specified by lower-priority MX records for the domain ) should implement the same greylisting policy and share the same database.
• The boundary MTA uses the Domain name system ( DNS ) to look up the mail exchanger record ( MX record ) for the recipient's domain ( the part of the email address on the right of @ ).
• In 2007, singer Yen reached the top 20 in the finals of Stefan Raab's music show SSDSDSSWEMUGABRTLAD . Yen has produced three albums and three singles in total and is signed to the Frankfurt indie label MX Records.
• It does say, in Section 5.1 : " When the lookup succeeds, the mapping can result in a list of alternative delivery addresses rather than a single address, because of multiple MX records, multihoming, or both.