Knowledge Base

Zimbra CSR Creation & SSL Installation Instructions

May 25, 2018 in Certificates

Create CSR on Zimbra and SSL Installation

Zimbra CSR Creation

  1. Log in as root.

  2. Adjust the following command to match your information: /opt/zimbra/bin/zmcertmgr createcsr comm -new '/C=US/ST=NJ/L=Clifton/O=Company Inc/OU=Department/CN=your.domain.com' Where:

    C = 2-digit country code

    ST = State/Province

    L = City

    O = Organization Name

    OU = Department (e.g., IT Department)

    CN = Common Name (mail.domain.com, *.domain.com)

    If you want to include more than one name in the CSR, you can add -subjectAltNames to the end of the command. Example:

    /opt/zimbra/bin/zmcertmgr createcsr comm -new '/C=US/ST=NJ/L=Clifton/O=Company Inc/OU=Department/CN=your.domain.com' -subjectAltNames 'www.domain.com, secure.domain.com'

  3. Running this command will output the CSR to the following location: /opt/zimbra/ssl/zimbra/comodo/comodo.csr

  4. You will use the CSR to place the order for the certificate (select “Other” as the server software when placing your order).

Zimbra SSL Installation

  1. Once you have received the .zip containing the certificate files, extract the “certs” folder somewhere on your server.

  2. Take your server certificate (your_domain_name.crt) and copy it to a file called comodo.crt in the following directory: /opt/zimbra/ssl/zimbra/comodo/

  3. With a text editor (such as wordpad or notepad), copy and paste the entire body of each of the following certificates into one text file in the following order:

    1. The First Intermediate Certificate - COMODORSAAddTrustCA.crt
    2. The Second Intermediate Certificate(if a 2nd intermediate cert is supplied) – COMODORSADomainValidationSecureServerCA.crt
    3. The Root Certificate - AddTrustExternalCAROOT.crt

    Make sure to include the beginning and end tags on each certificate. The result should look like this:

    -----BEGIN CERTIFICATE-----
    (Your First Intermediate certificate: ComodoRSAAddTrustCA.crt)
    -----END CERTIFICATE-----
    -----BEGIN CERTIFICATE-----
    (Your Second Intermediate certificate (if applicable): ComodoRSADomainValidationSecureServerCA.crt)
    -----END CERTIFICATE-----
    -----BEGIN CERTIFICATE-----
    (Your Root certificate: AddTrustExternalCARoot.crt)
    -----END CERTIFICATE-----

  4. Save the combined file as CACerts.crt in the following directory: /opt/zimbra/ssl/zimbra/comodo/

  5. Run the following command to validate the certificate chain: /opt/zimbra/openssl/bin/openssl verify -CAfile /opt/zimbra/ssl/zimbra/comodo/CACerts.crt

  6. Once the certificate chain is validated, you can run the following command to enable the new certificate for use: /opt/zimbra/bin/zmcertmgr deploycrt comm

The SSL certificate should now be active.

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