How to Install SSL Certificates on Zimbra Servers

Securing your Zimbra server with an SSL certificate is crucial for protecting user data and building trust. This guide offers a walkthrough on how to install SSL certificates on Zimbra servers, covering both methods: the Zimbra Administration Console and the Command Line Interface (CLI). Whether you prefer a user-friendly interface or a more technical approach, we'll equip you with the steps to successfully implement SSL encryption for your Zimbra environment.

In this article, we will discuss:

• Install SSL Certificates on Zimbra Servers
• Review

Install SSL Certificates on Zimbra Servers

There are two methods to install SSL Certificates on Zimbra servers:

• Via Zimbra Admin Console
• Via Command Line Interface (CLI)

Install SSL Certificates on Zimbra Servers Via Zimbra Admin Console

1. Log in to your Zimbra Admin Console using a browser
2. In the left navigation pane under Home, click Configure and then click Certificate.
   
3. On the right of the Zimbra Admin console, click on the settings icon and select Install Certificate.
4. The Certificate Installation Wizard will then pop up.
5. Under Server Name, select the Target server you will install the certificate for and then click Next.
   
6. Select the option, Install the commercial signed certificate, and then click Next.
   
7. If all the info in the review windows is correct, press Next.
8. Upload the files to their respective locations.
   
9. After uploading the files, click Install.
10. Restart the Zimbra services.

Once the restart is complete, you can now return to the Admin Console and view the installed Certificate.

Install SSL Certificates on Zimbra Servers Via CLI

If successful, you'll receive a response like <cert name>: OK

1. Your certificate ZIP file will be sent by email. The certificate ZIP is included as an attachment. The certificate file is also embedded in the body of the email.
2. Copy and paste the certificate into a text file (save as commercial.crt) using Vi or Notepad. Place this file in the following directory /opt/zimbra/ssl/zimbra/commercial/. The text file should look like this:

   -----BEGIN CERTIFICATE-----
   [encoded data]
   -----END CERTIFICATE-----

3. Open the CAbundle you received on a ZIP file using a text editor or Vi and save it as (commercial_ca.crt). Place this file in the following directory: /opt/zimbra/ssl/zimbra/commercial/.
   Note: If you are using notepad, then click Save as and in the save location window, choose 'save as' type as "ALL files", and give the file name as commercial_ca.crt.
4. Also, rename your private key file as commercial.key and move it to the same directory where we have placed other certificate files /opt/zimbra/ssl/zimbra/commercial/.
5. Now since you have all the files in the same directory, we can now enable the certificate. But first, let's Validate the Certificate Chain using the below command:
   /opt/zimbra/openssl/bin/openssl verify -CAfile commercial_ca.crt commercial.crt.
6. Finally, deploy your certificate using the following command: /opt/zimbra/bin/zmcertmgr deploycrt comm commercial.crt commercial_ca.crt.
7. Restart the Zimbra Services: zmcontrol restart.

Review

Securing your Zimbra server with an SSL certificate is critical to safeguard sensitive user data and bolster user trust. This guide has equipped you with the knowledge on how to install SSL certificates on Zimbra server using two methods: the Zimbra Administration Console, offering a user-friendly interface, and the Command Line Interface (CLI) for a more technical approach. Following these comprehensive instructions, you can successfully implement SSL encryption for your Zimbra environment, ensuring a secure and reliable communication channel.