Start with Disaster Recovery Chapter (Chapter 5) in NBU Troubleshooting Guide: http://www.symantec.com/docs/DOC3683
You will have to develop a DR plan for your unique environment - we cannot provide you with step-by-step instructions.
You need to know how to recover the NBU master server and/or media server(s), have all necessary backup data and devices available at DR site, identify critical systems that need to be recovered.
You may want to consider BMR for full system restores.
See BMR Admin Guide: http://www.symantec.com/docs/DOC3680
There are also lots of DR TechNotes and WhitePapers published by Symantec.
Herewith a list of TN's shared by Alex Davies at Vision in 2010:
http://www.symantec.com/docs/TECH50942 – conditions for support for catalog replication
http://www.symantec.com/docs/TECH66060 – guide to site recovery operations
http://www.symantec.com/docs/TECH125520 – replicating catalogs with non-clustered master servers
http://www.symantec.com/docs/TECH125519 – replicating catalogs with clustered master servers
http://www.symantec.com/docs/TECH125518 – recovery procedures for dual domain catalog replication
http://www.symantec.com/docs/TECH28722 – partial catalog recovery/recovery without import
http://www.symantec.com/docs/TECH72198 – recovering catalog backups from advanced disk storage
http://www.symantec.com/docs/TECH125784 – recovering catalog backups from duplicate copies
Some newer TNs:
http://www.symantec.com/docs/HOWTO75161 - About catalog recovery from disk devices in NetBackup 7.0 and 7.1
http://www.symantec.com/docs/HOWTO32925 - Recovering the entire NetBackup 7.0 or 7.1 catalog using bprecover -wizard
http://www.symantec.com/docs/TECH157454 - Catalog recovery from copy 2 on an OST device
http://www.symantec.com/docs/TECH127922 - More information about usage of the "nbcatsync"
So, there is no 'one-size-fits-all' DR solution.... You need go through all the available documentation and decide on a solution that will work for YOUR environment.
Then, do regular DR tests to perfect your own step-by-step process.