Jive SBS-managed databases will perform automatic backups as described in Auto Backups in the Platform Overview. In some situations, for example prior to an upgrade of the platform, you should perform a full database backup manually.
To manually perform a full backup of the managed database, execute the dbbackup script as the jive user.
[0801][jive@melina:~]$ ./bin/dbbackup /bin/tar: Removing leading '/' from member names
The command will not produce any further output if successful and will return zero if successful, non-zero otherwise.
You can restore from a backup by using PostgreSQL commands. In the PostgreSQL documentation, the section on recovering from your backup is probably the most specific. For a broader view, be sure to see the contents of their documentation on backing up and restoring.