RDF System Management Manual

Maintaining the Databases
HP NonStop RDF System Management Manual—524388-003
6-2
Understanding Database States
Figure 6-2 shows synchronized databases where the application is running on
\PRIMARY, three more transactions (T4, T5, T6) have occurred, and RDF is in the
process of applying the data records for these transactions to the backup system.
Transaction data for T4 has been applied to the backup database. The data for T5 is
still being applied to the backup database, and the data for T6 has not yet been sent to
the backup system.
Although transactions T5 and T6 have not yet been applied to the backup database,
the primary and backup databases are synchronized in that the only thing delaying the
two databases from being logically identical is the second or so it takes the extractor
and updaters to catch up with the MAT.
Figure 6-2. Synchronized Databases During RDF Operations
MAT
Image File
Database Database
\PRIMARY \BACKUP
T1
T2
T3
T4
T5
T6
T4 T5 T6
T4 T5
T1
T2
T3
T4
Updater
Extractor