can someone help me to understand the difference between
~all and -all in DNS SPF record ?
This article should help: http://www.openspf.org/SPF_Record_Syntax
In brief, "~" indicates a Soft Fail and "-" indicates a Hard Fail. If you use ~all, mail that violates the rule will be accepted but marked, whereas -all will drop any mail that violates the rule.
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