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Spamd
Jul 20, 2023
Traps spammers with a very slow smtp-login and return 4xx error
Spamd is a fake sendmail8-like daemon which rejects false mail. It is designed to be very efficient so that it does not slow down the receiving machine.
spamd considers sending hosts to be of three types
blacklisted hosts are redirected to spamd and tarpitted i.e. they are communicated with very slowly to consume the sender’s resources. Mail is rejected with either a 450 or 550 error message. A blacklisted host will not be allowed to talk to a real mail server.
whitelisted hosts do not talk to spamd. Their connections are instead sent to a real mail server, such as sendmail8.
greylisted hosts are redirected to spamd, but spamd has not yet decided if they are likely spammers. They are given a temporary failure message by spamd when they try to deliver mail.
Checkout these related ports:
- Xpbiff -
- Xmailwatcher - Mailbox checker which displays sender and subject lines of mails
- Xmailbox - Mailbox checker with sound and animation for X Window System
- Xmail - X-based interface to the Berkeley mail program
- Xfce4-mailwatch-plugin - Mail notification applet for the Xfce panel
- Xfaces - Display shaped icons for mail spool contents
- Xcite - Exciting Cite for any Mail/News reading modes on Emacs
- Xbuffy - Replacement for xbiff that handles multiple mail files
- X-face-e21 - X-Face utilities for Emacs
- Wmmaiload - Incoming mail monitor dockapp with a similar look to wmcpuload
- Wmbiff -
- Whoson - Implementation of `WHO iS ONline' protocol
- Websieve - Web based Cyrus IMAP user admin client
- Wanderlust - Mail and news system for Emacs
- Vrfy - Verify mail address