The documentation you linked is related to DLP rather than an encryption product.
I assume you're speaking about upgrading the Symantec Encryption Management Server (SEMS). If you're looking to update to a minor revision, you can use the PUP update files that should be available in your Broadcom products page.
If you are jumping a major version (from
3.3.x to
3.4.x, or from
3.4.x to
10.5), you would need to capture a backup of your existing
Database and
Organization Key and get the files off the server via SSH/SCP, install the new version you wish to have, then restore the backup to it.
More information about this is in the
SEMS Upgrade Guide.