Moved discussion to the Server Automation Product Community.
That link seems to be broken. Here is the link for BSA "High availability and disaster recovery"
To simplify, there are 3 major components to BSA:
- File Server
- Application Servers
HA for the Database typically involves clustering. HA for the File Server storage is trypically a NAS or SAN share. You want to have two or more Application Servers and connect to them from your Console via a VIP (or Round Robin DNS) which will alternate which App Server you log in to. BSA will automatically spread Jobs over your App Servers so if one goes down, the others will continue to run Jobs.