How important are PTR records for Email Servers?

Posted by Kyle Brandt on Server Fault See other posts from Server Fault or by Kyle Brandt
Published on 2009-12-09T15:02:27Z Indexed on 2010/04/04 17:33 UTC
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Filed under:

ptr

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dns

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reverse-dns

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email

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smtp

Does anyone know of any studies done to show how much email will be rejected if there is not ptr record for the SMTP banner name of an email server?

Are reverse checks always done when enabled, or is it sometimes configured so if an spam program considers an email 'iffy', the reverse check is done?

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