Table of Contents

1. Challenge

   Install and configure Sieve

   Our first step is to edit:

   vim /etc/dovecot/conf.d/15-lda.conf
   

   Find the protocol lda section and ensure it looks like this:

   protocol lda {
     # Space separated list of plugins to load (default is global mail_plugins).
     mail_plugins = sieve
   }
   

   Now configure postfix:

   vim /etc/postfix/main.cf 
   

   Find the mailbox_command setting and set it to use the dovecot specific delivery binary:

   mailbox_command = /usr/libexec/dovecot/deliver
   

   Install Sieve:

   yum install dovecot-pigeonhole -y
   

   vim /etc/dovecot/conf.d/90-plugin.conf
   

   Set the plugin up like so:

   plugin {
     # setting_name = value
       sieve=~/.dovecot.sieve
       sieve_dir = ~/sieve
       sieve_global_dir = /home/sieve
       sieve_max_script_size = 1M
   }
   

   Now we need to edit dovecot's config again:

   vim /etc/dovecot/dovecot.conf
   

   The protocols line should include the sieve plugin:

   protocols = imap sieve
   

   Edit the 20-managesieve.conf file and uncomment the following lines:

   vim /etc/dovecot/conf.d/20-managesieve.conf
   
   service managesieve-login {
     inet_listener sieve {
       port = 4190
     }
   

   Now we can build our Sieve script:

   vim /home/test_user/.dovecot.sieve
   

   Your script should look something like this:

   require "fileinto";
   
   if header :contains "Subject" "WORK" {
           fileinto "Work";
   }
   

   Restart postfix and dovecot:

   systemctl restart postfix
   systemctl restart dovecot
   

   Sieve is configured!

2. Challenge

   Test your Sieve script

   1. To test your sieve script, you should send a test email.

   telnet localhost 25
   Trying ::1...
   Connected to localhost.
   Escape character is '^]'.
   220 server1.example.com ESMTP Postfix
   ehlo localhost
   250-server1.example.com
   250-PIPELINING
   250-SIZE 10240000
   250-VRFY
   250-ETRN
   250-ENHANCEDSTATUSCODES
   250-8BITMIME
   250 DSN
   mail from: [email protected]
   250 2.1.0 Ok
   rcpt to: [email protected]
   250 2.1.5 Ok
   data
   354 End data with <CR><LF>.<CR><LF>
   Subject: WORK
   .
   250 2.0.0 Ok: queued as 3CA4197CBF
   

   2. Once sent, copy the message ID (the number after "queued as" above) and use it to grep the mail log:

   [root@server1 test_user]# grep 3CA4197CBF /var/log/maillog
   Jun  8 06:22:53 server1 postfix/smtpd[12092]: 3CA4197CBF: client=localhost[::1]
   Jun  8 06:22:59 server1 postfix/cleanup[12096]: 3CA4197CBF: message-id=<[email protected]>
   Jun  8 06:22:59 server1 postfix/qmgr[1670]: 3CA4197CBF: from=<[email protected]>, size=323, nrcpt=1 (queue active)
   Jun  8 06:22:59 server1 dovecot: lda(test_user): sieve: msgid=<[email protected]>: stored mail into mailbox 'Work'
   Jun  8 06:22:59 server1 postfix/local[12097]: 3CA4197CBF: to=<[email protected]>, relay=local, delay=16, delays=16/0.01/0/0.08, dsn=2.0.0, status=sent (delivered to command: /usr/libexec/dovecot/deliver)
   Jun  8 06:22:59 server1 postfix/qmgr[1670]: 3CA4197CBF: removed
   

   As you can see, the 4th line indicates that Sieve sorted the email into the correct folder. Congratulations!