How To Configure Receive Email From The Internet/Outside

Home » Zimbra » How To Configure Receive Email From The Internet/Outside
Zimbra 5 Comments

After installing Zimbra as described at this guidance : installing Zimbra on CentOS 6 or install Zimbra on CentOS 7, by default we could sent email to outside/internet if have the internet connection and port 25 outgoing is not blocked by firewall or blocked by ISP connection. After that, usually try to receive email from internet/outside and never coming to Zimbra that has been installed. This problem occurs because some information below :

1. We should have the real domain that known on the internet. You can bought a domain from Godaddy or other provider

2. We should have at least one Public IP. You can rent a VPS from Digital Ocean or other provider and then install Zimbra in it

3. We should have dns management for configure A and MX Records. If you also bought hosting on your domain provider, usually you can manage dns on cPanel or something else. If you bought a domain only, you could using Free DNS management from Hurricane up to 50 domain and configure your domain nameserver to refer to Nameserver of Hurricane.

In this section, i have a domain that has been bought from Godaddy and have 1 Public IP and dns management on cPanel (Hosting from Excellent Infotama Kreasindo Inc). This is what i do for a configuration to receive emails from internet/outside

# Configure A Records on DNS Management (cPanel)

Select Advanced DNS Zone Editor and add A records (see the following picture)


After adding A records, please check for dns propagation at this link : whether name (you can using another name) has been known in the internet or still propagate

# Configure MX Records on DNS Management (cPanel)

After configure A Records on cPanel, go to home and select MX Entry. If you have been saw existing MX records using 0 (zero) priority, change it to 50 or 20 (or you can remove it if not needed). Add MX records to refer to the name who has been configured formerly and give 10 priority.


After adding MX records, please check for dns propagation at this link : whether the new MX records for domain has been known in the internet or still propagate.

After above configuration has been configured, you should be able to receive emails from internet/outside.

Good luck and hopefully useful 😀

5 thoughts on - How To Configure Receive Email From The Internet/Outside

  • Hi Iman,

    Thank you for your note.. Really a nice one…. I followed the procedures of installation and in my domain i am receiving the mails from other domain but i am not able to send mails to other domains. I have valid MX and PTR. Kindly need your help on this…

    • Hello Manikumar,

      For sending email to outside, you should :
      1. Use static IP
      2. Open port 25 outgoing
      3. Nothing firewall for port 25 outgoing

      For testing port 25 out, please paste the result from the following command

      telnet 25
  • Hi Iman,
    In my network i am having 2 ISP’s. As of now i configured everything in network 1 and i would like to do whenever the network 1 is goes down network 2 should live. Please help me on this.

  • HI iman,
    I install zimbra 8.6 on centos 7. My mail was sending /receiving even on outside network (internet) but i cant send to other domain without smtp relay.. do I really need to have it? How can I send to other domain using my own MTA(without relay)? Thanks..

    • Hi,
      By default, you can direct sending email into outside without relay. But, if your public IP was blacklisted anywhere, you should use smtp relay