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hints:classic_linux_mail_flow

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hints:classic_linux_mail_flow [2021/03/05 17:26]
admin [Run Procmail and SpamAssassin]
hints:classic_linux_mail_flow [2021/04/03 07:41] (current)
admin [Receive a message from the network]
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   * Accept the message because it contains no spam and no virus.   * Accept the message because it contains no spam and no virus.
  
-Postfix acts on these findings. It will send a permanent rejection reply to the remote SMTP client due to a virus or guaranteed spam, or do greylisting by sending a temporary rejection to the remote SMTP client (which means try again later).((Most infected Microsoft Windows machines that are part of a botnet being used to send spam will not retry sending the same spam message, so greylisting eliminates almost all spam sent by such machines. The next time the same client sends a message from the same sender to the same recipient, within a predetermined period, it will not be greylisted.)), or accept the message from the remote SMTP client. Due to the high incidence of spam and viruses, only about 20% of incoming mail is unconditionally accepted. Most is rejected outright, and some is greylisted.+Postfix acts on these findings. It will send a permanent rejection reply to the remote SMTP client due to a virus or guaranteed spam, or do greylisting by sending a temporary rejection to the remote SMTP client (which means try again later)((Most infected Microsoft Windows machines that are part of a botnet being used to send spam will not retry sending the same spam message, so greylisting eliminates almost all spam sent by such machines. The next time the same client sends a message from the same sender to the same recipient, within a predetermined period, it will not be greylisted.)), or accept the message from the remote SMTP client. Due to the high incidence of spam and viruses, only about 20% of incoming mail is unconditionally accepted. Most is rejected outright, and some is greylisted.
  
 If Postfix accepts the message, it expands aliases and domain names until it determines the final recipient, which in Classic Linux is always a Linux user. Let's call that user the first user, also called USER. If Postfix accepts the message, it expands aliases and domain names until it determines the final recipient, which in Classic Linux is always a Linux user. Let's call that user the first user, also called USER.
hints/classic_linux_mail_flow.txt ยท Last modified: 2021/04/03 07:41 by admin