Where/How to download licensed NetBackup 6.5 software.
http://seer.entsupport.symantec.com/docs/308714.htm
and also check the OS Compatibility matrix for NetBackup to see what server OS NOM can manage and be managed by.
See at the NB support home page for matrix
http://www.symantec.com/business/support/overview.jsp?pid=15143