Broadcom doesn't certify Operating System Level Patches.
Release : 10.4.x 20.2.x 21.2.x
Component : SPCCRT : Spectrum Certification
Broadcom will certify the product with Operating System Versions (Ex: Windows 2016, RHEL 7.x) not at patch level.
Patches need to be tested in Test Environment before applying on to the Production Environment.
Take necessary backups
How to backup the the Archive Manager (DDM) database
How to Backup and Restore CA Spectrum Reporting Manager Database .
What is the best practice to make a complete backup copy of SPECTRUM?
Backup custom folder
%SPECROOT%\custom from each box in your environment.
Gracefully shutdown the services before Upgrading or rebooting the server.
Now you can apply the patches
Start the services.