For disaster recovery of SEPM server 11.x as per kb "http://www.symantec.com/business/support/index?page=content&id=TECH102333"
there is one of step
Reinstalling the Symantec Endpoint Protection Manager
The key task to perform when you reinstall the Symantec Endpoint Protection Manager is to type the same encryption password you specified during installation
of Symantec Endpoint Protection Manager on the server that failed. You should also use the same settings that you used for other options during the previous
installation, such as Web site creation, database type, and password used for the admin user account.
Now we are preparing for disaster reocery for SEP 11.x we collecting info as per article from above steps where we get encryption password if we foregot the password which we have put during installation done because installation has been done long time back.