Txt v spf1 a

Better names for this mechanism would have been "if-pass", "on-pass", etc. Modifiers are optional. A modifier may appear only once per record.

Unknown modifiers are ignored. The SPF record for domain replace the current record. The macro-expanded domain is also substituted for the current-domain in those look-ups. If an SMTP receiver rejects a message, it can include an explanation.

An SPF publisher can specify the explanation string that senders see. The domain is expanded; a TXT lookup is performed. The result of the TXT query is then macro-expanded and shown to the sender. Other macros can be used to provide an customized explanation. Forums Tools. Perhaps example. If example. Similarly for offsite. For example, hotmail. If it does resolve, this mechanism results in a match. Look up the A record for example. If it matches 1. If there is no match, other than the included domain's " -all ", the include as a whole fails to match; the eventual result is still Fail from the outer directive set in this example.

One of the most important records that we need to set up to make sure that our emails will be delivered fine is the SPF record. This a kind of DNS record widely used, in fact, all the websites that have their own email accounts need to use a record like this, otherwise, their email may never reach the destination. SPF records are important because of two things: avoiding spoofing issues and avoiding spam issues.

Probably many of you have heard about email spoofing. What is email spoofing exactly? That way, that person is sending an email pretending to be you. Spoofing is a very common practice among spammers and people looking to stole date through phishing. The other important topic regarding SPF records is being marked as spam. These define the rules for which hosts are allowed to send mail from the domain, or provide additional information for processing the SPF record.

Terms are made up of mechanisms and modifiers. The following mechanisms are defined:. A mail server will compare the IP address of the sender against the IP addresses defined in the mechanisms. If the IP address matches one of the mechanisms in the SPF record then follow the result handling rule. The include mechanism allows you to authorize hosts outside of your administration by specifying their SPF records. The all mechanism matches any address.