Data Stream as a stand alone product is not disaster tolerant but works in conjunction with industry leading products to form a disaster recovery process.
Data Stream recommends the use of Ola Hallengren Scripts.
Download the scripts here.
When the mirrored database is synchronized, the database owner or system administrator can initiate manual fail-over to the secondary server.
USE master;GOALTER DATABASE [DataStream] SET PARTNER FAILOVER;
Automatic fail-over occurs when the fast startup is disabled and computer is properly shutdown.