By now, everyone should know that I am a "diagram" guy. I do not like to read words after words, if a simple diagram can do the job. That's just me. :)
So, how do we go about upgrading CA SiteMinder to the latest r12.5?
The strategy is simple:
0. Do not touch the Policy/Key Store
1. Start with Policy Server upgrade
2. Proceed with Web Agent upgrade (Note: This new agent must talk to the new Policy Server)
3. Repeat until all components are upgraded
4. We are now ready to replace the Policy/Key Store
That's it! Simple.