This solution applies to all Barracuda SSL VPNs.
From the appliance web interface, navigate to Basic > SSL Certificate and fill in the required fields for generating a Certificate Signing Request (CSR) under the Certificate Generation header. Once the CSR is generated and submitted to GeoTrust, they will send back a signed certificate that has a .cer file extension. You will also need to obtain a root certificate from the GeoTrust website, and download the private key from the same page you downloaded the CSR on the Barracuda appliance.
Proceed to upload the signed certificate, root certificate, and the private key under the Trusted Certificate header. Once you have entered the files in the appropriate fields, click Upload Certificate and Key to commit the changes. Select Trusted Certificate in the Certificate Type section. Click on the Synchronize button as your final step.
Upload Signed Certificate: cuda.domain.tld.cer (from GeoTrust).
Upload Certificate Chain Bundle: GeoTrustRoot.cer (from https://www.geotrust.com/resources/root-certificates/).
Upload Backup SSL Private key: private.key (downloaded from certificate generation section).
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