efa error 450.4.7.1 client host rejected: cannot find your reverse hostname

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fatima2007
Posts: 32
Joined: 03 Jan 2018 11:14

efa error 450.4.7.1 client host rejected: cannot find your reverse hostname

Post by fatima2007 »

hi dears
newly i have a problem with efa. one organization sent me several emails but my email server didnt receive their emails. i check efa logs. i see this error : 450.4.7.1 client host rejected: cannot find your reverse hostname
i add this address to whit list. i check my dns. and my problem didnt resolve. i serach in internet. i check that organization ip address. i see their ip have not reverse dns. because of this my efa reject their emails. my question is how can i tell efa that do not reject this ip and all ips that have not reverse address?

thanks a lot
budy
Posts: 74
Joined: 10 Sep 2017 07:33

Re: efa error 450.4.7.1 client host rejected: cannot find your reverse hostname

Post by budy »

Hi,

although I would not recommend doing this, because the current setting will prevent a slew of botnetted hosts from delivering spam and malware to your MTA, this can be switched off in postfix. This check takes place right at the start of the smtp conversation, even before the sender is evaluated and it is a good thing to have. However, if you want to switch that off, read up on that restriction in postfix. Switching that one off is so much against me, that I even won't make it easy for you, by providing you further advice on how to do that - maybe you can think about that while you research the relevant docs for postfix.

Admins of MTAs should have a obligation to make sure that their MTAs resolve cleanly forward and reverse.

Cheers,
budy
fatima2007
Posts: 32
Joined: 03 Jan 2018 11:14

Re: efa error 450.4.7.1 client host rejected: cannot find your reverse hostname

Post by fatima2007 »

thank you very much. could i exclude a specific domain from this checking?
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