On 31.03.20 16:59, Linda Pagillo wrote:
Guys, I have another question. This is in reference to the response that Bob Proulx gave me. He said that, " One critical item is that the relay_recipient_maps must be kept in sync across all of the systems". Why is this critical?
It's partly described at http://www.postfix.org/postconf.5.html#relay_recipient_maps many spammers try to use backup MX servers to deliver spam. If your backup MX accepts spam that your primary MX would rejects because of non-existent user, your backup MX would need to send back bounce, which whould make it spam source, and it could appear on blacklists. Dropping such mail is not a good thing, since that mail could get "lost" where sender believe mail was accepted (by backup MX), while recipient would not see it (because it was refused by primary MX). Thus, knowing users is crucial to have. I persinally believe that if you really need backup MX, you should do at least some kind of recipient verification. -- Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/ Warning: I wish NOT to receive e-mail advertising to this address. Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. Windows 2000: 640 MB ought to be enough for anybody