Membuat Server MX Backup dengan Postfix

Dalam mengoperasikan mail server mungkin saja ada gangguan pada mail server utama misalnya incoming port 25 tertutup. Untuk mengatasinya kita membuat server mx backup dan kemudian meneruskan ke server utama melalui port lain.

Membuat Server untuk MX Backup dengan Postfix adalah seperti pada berikut ini

1. Silahkan instal postfix dengan tipe Internet Site
2. Pada /etc/postfix/main.cf bagian restriction

   smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination

3. Pada

   relay_domains = $mydestination, domainku.com 

4. Pada

   relay_recipient_maps =

5. Seting relay host ke server utama melalui port lain

   relayhost = [204.233.95.52]:1190

6. Contoh lengkap konfigurasi lengkap

   # See /usr/share/postfix/main.cf.dist for a commented, more complete version
   
   
   # Debian specific:  Specifying a file name will cause the first
   # line of that file to be used as the name.  The Debian default
   # is /etc/mailname.
   #myorigin = /etc/mailname
   
   smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
   biff = no
   
   # appending .domain is the MUA's job.
   append_dot_mydomain = no
   
   # Uncomment the next line to generate "delayed mail" warnings
   #delay_warning_time = 4h
   
   readme_directory = no
   
   # See http://www.postfix.org/COMPATIBILITY_README.html -- default to 2 on
   # fresh installs.
   compatibility_level = 2
   
   
   
   # TLS parameters
   smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
   smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
   smtpd_tls_security_level=may
   
   smtp_tls_CApath=/etc/ssl/certs
   smtp_tls_security_level=may
   smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
   
   
   #smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
   smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination
   myhostname = server3.ult.id
   alias_maps = hash:/etc/aliases
   alias_database = hash:/etc/aliases
   myorigin = /etc/mailname
   mydestination = $myhostname, server3.ult.id, localhost.ultima.id, , localhost
   relay_domains = $mydestination, tokokue.com
   relay_recipient_maps =
   relayhost = [209.233.95.52]:1190
   mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
   mailbox_size_limit = 0
   recipient_delimiter = +
   inet_interfaces = all
   inet_protocols = all
   
   

Informasi lebih lanjut silahkan mengunjungi
1. https://www.howtoforge.com/postfix_backup_mx .
2. https://askubuntu.com/questions/1331555/which-option-internet-site-internet-with-smarthost-satellite-system-sh .
3. https://www.postfix.org/documentation.html .

Kunjungi www.proweb.co.id untuk menambah wawasan anda.