[Ubuntu] 架設郵件伺服器 (Postfix + Dovecot)

Postfix

1. sudo hostnamectl set-hostname a1go.ai
2. hostname -f確認 hostname

3. sudo apt install postfix

   1. General mail configuration type: Internet Site
   2. System mail name: a1go.ai
4. DNS setting¹Namecheap:
   MAIL SETTINGS → Custom MX
   → Type: MX Record　|　Host: @　|　Mail Server: a1go.ai　|　Priority: 0　|　TTL: Automatic

※ Postfix 的 log 在 /var/log/mail.log

Dovecot

1. sudo apt install dovecot-core dovecot-lmtpd
2. sudo useradd vmail
3. sudo mkdir /var/mail/vhosts
sudo chown vmail:vmail /var/mail/vhosts (把 owner 和 group 的 ownership 都改成vmail)
4. sudo nano /etc/dovecot/conf.d/10-mail.conf
   修改 mail_location = maildir:/var/mail/vhosts/%d/%n
   (user@domain – %n: user part, %d: domain part)
5. sudo nano /etc/dovecot/conf.d/10-auth.conf
   1. !include auth-system.conf.ext → #!include auth-system.conf.ext
   2. #!include auth-static.conf.ext → !include auth-static.conf.ext
6. sudo nano /etc/dovecot/conf.d/auth-static.conf.ext 加入：

   # static userdb with shared uid and gid
   userdb {
     driver = static
     args = uid=vmail gid=vmail
   }
   
   # using password file
   passdb {
     driver = passwd-file
     args = /etc/dovecot/passwd
   }

7. 新增 Dovecot User：
   sudo sh -c "echo {user}@{domain}:{passwd}:::::: >> /etc/dovecot/passwd"
8. sudo nano /etc/dovecot/conf.d/10-master.conf將以下部分

   service lmtp {
     unix_listener lmtp {
       #mode = 0666
     }
   
     ...
   }

   改動為：

   service lmtp {
     unix_listener /var/spool/postfix/private/dovecot-lmtp {
       mode = 0600
       group = postfix
       user = postfix
     }
   
     ...
   }

9. sudo nano /etc/postfix/main.cf加入：

   virtual_mailbox_domains = a1go.ai
   virtual_transport = lmtp:unix:private/dovecot-lmtp

   還要把 virtual_mailbox_domains(a1go.ai) 從 mydestination 刪除：
   mydestination = localhost # $myhostname, a1go.ai, localhost.ai, , localhost

10. sudo service postfix restart
sudo /etc/init.d/dovecot restart

※ 讀取信件
sudo doveadm fetch -u {user}@{domain} text.utf8 MAILBOX INBOX

Ref

1. Dovecot Manual

Last Updated on 2023/10/19 by A1go

References

• 1
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