Configserver provides a very effective and usefull feature to avoid Brute-force attacks. This daemon runs all the time and periodically scans latest log files for login attempts against your server. Such attempts are often called "Brute-force attacks" and the daemon process responds very quickly to such patterns and blocks offending IP's quickly.
Login tracking is an extension of lfd, it keeps track of POP3 and IMAP logins and limits them to X connections per hour per account per IP address.
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