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| SPF sender policy framework |
SPF RECORDS
SPF "Sender Policy Framework". As with all three checks. SPF is a DNS TXT record that specifies which IP addresses and/or servers are allowed to send email from that particular domain. SPF sender policy framework
If they know who sent them the letter, the recipient is more likely to open it.
An SPF record is only neccessary for the top level domain ( i.e., your-domain.com ). An SPF record for a top level domain automatically authenticates any subdomains under it (eg., mail.your-domain.com). SPF sender policy framework checker
Cannot generally exceed 255 characters.
SPF record format
SPF records are typically defined using the TXT record type. There’s also an SPF record type, but it’s deprecated, and you should always have at least the TXT record definition present, even if you use the SPF type.SPF records are defined as a single string of text. Here’s an example record:
v=spf1 a mx ip4:69.64.153.131 include:_spf.google.com ~all
The SPF record always starts with the v= element. This indicates the SPF version that is used. Right now the version should always be spf1 as this is the most common version of SPF that is understood by mail exchanges.
One or more terms follow the version indicator. 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:
- all
- include
- a
- mx
- ip4
- ip6
- exists
The ptr type is also defined but shouldn’t be used.
There are two modifiers defined:
- redirect
- exp
SPF mechanisms
The following mechanisms define what IP addresses are allowed to send mail from the domain:- a
- mx
- ip4
- ip6
- exists
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 default handling rule is + or pass.
The include mechanism allows you to authorize hosts outside of your administration by specifying their SPF records.
The all mechanism matches any address. This is usually used as the last mechanism which defines how to handle any sender IP that did not match the previous mechanisms.
All mechanisms may specify qualifiers for how to handle a match:
- + for pass
- - for fail
- ~ for soft fail
- ? for neutral
As previously mentioned, the default handling rule is pass, which is the same as the + qualifier.
SPF modifiers
Modifiers are name/value pairs (separated by an = sign) that provide additional information. Modifiers should appear at the end of the SPF record. A modifier may not appear more than once and unrecognized modifiers are ignored.
The redirect modifier is used to point to another SPF record to use for processing. This is used when you have multiple domains and want to apply the same SPF content across those multiple domains. Redirects should only be used if you control both domains, otherwise an include is used.
The exp modifier is used to provide an explanation in case of a - (fail) qualifier is present on a mechanism that is matched.
Note that we currently do not support modifiers in our SPF editing UI, but you may always add them if you are managing your SPF TXT record directly
Check SPF Record
In order to implement SPF you will need to have a valid SPF record. DMARC Analyzer provides a SPF Record Checker to validate your SPF record.We can also pre-validate an update you intend to apply to your record to prevent issues popping up after the update was done. We recommend you to carefully test any updates to your SPF records before applying them.
Click Here :- SPF Record check
