Managing Serviceguard Extension for SAP, December 2007

SAP Supply Chain Management
More About Hot Standby
Chapter 4206
The liveCache logging gets continuously verified during operation. An
invalid entry in the log files gets detected immediately. This avoids the
hazardous situation of not becoming aware of corrupted log files until
they fail to restore a production liveCache instance.
A data storage corruption that could happen during operation of the
master does not get replicated to the only logically coupled standby. The
standby LUNs used for devspace content do not necessarily keep the
same data as the master LUNs. At least not on a physical level. But
logically the standby keeps consistency and stays close to the content of
the master LUNs. The standby can then be promoted to become the new
master immediately. With access to the original log of the master, it is
able to update itself without any data loss.