The SSO configuration is ONLY used where you are sharing a SAN connected tape libray to more then one media server
To backup data on a SAN disk attached to a server, you make that server into a media server and then attach the backup storage devices to that server (over SAN technology if applicable) and then just configure a normal backup job
The other option is to consider the ADBO Off Host option (which depends on supported SAN hardware and configuration)
You should possibly take a look at this blog which may help you understand some of the SAN capabiities
https://www-secure.symantec.com/connect/blogs/lan-free-including-san-backup-configurations-backup-exec
