This method starts extraction and transmission when the source Datareplicator starts. When the simultaneous start method is used, update information is sent from the system log file in the order it is extracted.

• Purpose
  This method is appropriate for sending update information from the system log file to the target system in the order it is extracted.
  
• Command execution
  Execute the hdestart command.
  

This method starts only extraction processing when the source Datareplicator starts and starts transmission processing when it is requested by entry of the hdestart -s command. The transmission delay start method is used when the target system has not started or to avoid performing extraction processing when the target system's workload is high.

When the transmission delay start method is used, the update information stored in the extraction information queue file is not sent; instead, the extracted update information is stored. Therefore, you must allocate a sufficient space for the extraction information queue file.

• Purpose
  This method is appropriate when the target system has not started or to delay extraction processing start at a time when the target system's workload is high.
  

Command execution

Execute the hdestart -e command. To start transmission processing, execute the hdestart -s command. By specifying a target identifier in the hdestart -s command, you can start transmission to a specified destination.

This method starts only transmission processing when the source Datareplicator starts and starts extraction processing when it is requested by entry of the hdestart -e command. The extraction delay start method is used when the source HiRDB's online workload is important.

When the extraction delay start method is used, the system log file will not be placed in extraction completed status (it will not be swappable) because Datareplicator does not extract update information from the source HiRDB's system log file. If a large amount of transaction processing is expected at the source HiRDB, you must allocate a sufficient space for the system log file.

• Purpose
  This method is appropriate when the source HiRDB's online workload is important.
  
• Command execution
  Execute the hdestart -s command. By specifying a target identifier in the hdestart -s command, you can start transmission to a specified destination. To start extraction processing, execute the hdestart -e command.