The simultaneous start method starts import processing simultaneously with startup of the target Datareplicator. This method enables you to import update information in the order it is received. Figure 6-17 shows an example of target Datareplicator operation using the simultaneous start method, and Table 6-9 explains the handling procedure and target Datareplicator processing when the simultaneous start method is used.

Figure 6-17 Example of target Datareplicator operation using the simultaneous start method

Note: The numbers in the figure (1 and 2) correspond to the numbers in Table 6-9.

Table 6-9 Handling procedure and target Datareplicator processing (simultaneous start)

No.	Handling procedure	Target Datareplicator processing
1	Execute the hdsstart command (for an initial startup, execute hdsstart -i command).	The target Datareplicator starts and begins receiving and importing update information sent from the source system.
2	Execute the hdsstop command.	The target Datareplicator terminates after importing all update information for the source system's online application (equivalent to one session).

Definition example

The following is an example of the import environment definition for starting the target Datareplicator with the simultaneous start method:

set startmode=trn

This method starts import processing after a user-specified amount of time elapses since startup of the target Datareplicator. Figure 6-18 shows an example of target Datareplicator operation using the delayed start (time-specified start) method, and Table 6-10 explains the handling procedure and target Datareplicator processing when the delayed start (time-specified start) method is used.

Figure 6-18 Example of target Datareplicator operation using the delayed start (time-specified start) method

Note: The numbers in the figure (1 through 3) correspond to the numbers in Table 6-10.

Table 6-10 Handling procedure and target Datareplicator processing (delayed start (time-specified start) method)

No.	Handling procedure	Target Datareplicator processing
1	Execute the hdsstart command.	The target Datareplicator starts and begins receiving update information sent from the source system.
2	--	The target Datareplicator automatically starts import processing 1 hour and 30 minutes after its startup.
3	Execute the hdsstop command.	The target Datareplicator terminates after importing all update information for the source system's online application (equivalent to one session).

Legend:

--: No action is needed.

Definition example

The following is an example of the import environment definition for starting the target Datareplicator with the delayed start (time-specified start) method, where the target Datareplicator starts import processing using the table-based import method 1 hour and 30 minutes after its startup:

set startmode=spd set breaktime=01:30 set breakmode=tbl

This method starts the import processing by executing a command in the source system.

To start the target Datareplicator by using the delayed start method (command start method):

1. Specify spd in the startmode operand in the import environment definition.
2. Execute the hdsstart command at the target system to start the target Datareplicator. Only reception processing beings according to the import environment definition.
3. Execute the hdsrfctl -m trn or hdsrfctl -m tbl command at the target system. Import processing begins using the specified import method.

This method starts import processing when an event from the source system is detected. Figure 6-19 shows an example of target Datareplicator operation using the delayed start (event start) method, and Table 6-11 explains the handling procedure and target Datareplicator processing when the delayed start (event start) method is used.

Figure 6-19 Example of target Datareplicator operation using the delayed start (event start) method

Note: The numbers in the figure (1 through 3) correspond to the numbers in Table 6-11.

Table 6-11 Handling procedure and target Datareplicator processing (delayed start (event start) method)

No.	Handling procedure	Target Datareplicator processing
1	Execute the hdsstart command.	The target Datareplicator starts and begins receiving update information sent from the source system.
2	--	The target Datareplicator starts import processing when it detects an event corresponding to the import restart event.
3	Execute the hdsstop command.	The target Datareplicator terminates after importing all update information for the source system's batch application (equivalent to one session).

Legend:

--: No action is needed.

Definition example

The following is an example of the import environment definition for starting the target Datareplicator with the delayed start (event start) method, where the target Datareplicator starts import processing using the transaction-based import method after receiving an event with event code 1:

set startmode=spd set eventretrn=1

To terminate import processing while keeping reception processing active:

1. Execute the hdsrfctl -m spd command at the target system.
2. Generate an event at the source system. Import processing stops when the target system detects the event. For details about how to issue events at the source system when the source database is a HiRDB, see the hdeevent command (issue an event at the source Datareplicator) in 7. Command Syntax. For details about how to issue events at the source system when the source database is a mainframe database, see the VOS3 XDM/DS manual.

Alternatively, execute the hdsrfctl -m immediate command at the target system.

If import processing has stopped due to an import definition error or an SQL error, or if only reception processing was activated during startup, you can restart import processing only by specifying the desired import processing method.

To restart import processing by specifying an import processing method:

1. Execute the hdsrfctl -m trn or hdsrfctl -m tbl command at the target system.
2. At the source system, generate an event corresponding to the eventretrn or eventretbl operand in the import environment definition. When the target system detects the event, import processing is restarted by means of the specified method.

You can stop import processing while data linkage processing is underway in accordance with the import environment definition, and then restart processing at a desired time using a different import method (transaction-based import method or table-based import method).

To switch the import method during operation:

1. Execute the hdsrfctl -m spd command at the target system to stop import processing.
2. Execute the hdsrfctl -m trn or hdsrfctl -m tbl command at the target system.
3. At the source system, generate an event that corresponds to the eventtrn or eventtbl operand in the import environment definition. The import method is switched when the target system detects the event generated at the source system.

Figure 6-20 shows an example of operation involving switching of the import method, and Table 6-12 explains the handling procedure and target Datareplicator processing when the import method is switched.

Figure 6-20 Example of operation to switch the import method

Note: The numbers in the figure (1 through 4) correspond to the numbers in Table 6-12.

Table 6-12 Handling procedure and target Datareplicator processing (switching the import method)

No.	Handling procedure	Target Datareplicator processing
1	Execute the hdsstart command.	The target Datareplicator starts and begins receiving and importing update information sent from the source system (online application).
2	Execute the hdsrfctl -m spd command before terminating import of update information for the online application (in accordance with the import environment definition, the target Datareplicator is to change to the table-based import method to resume import processing when it finishes importing update information for the online application).	The target Datareplicator terminates only the import processing after detecting an event (event code = 2). (If executed, the hdsrfctl command takes precedence over the specification of eventtbl=2 in the import environment definition.)
3	Execute the hdsrfctl -m trn command before terminating reception of update information for the batch application.	When the command is executed, the target Datareplicator restarts import processing on the update information for the batch application.
4	Execute the hdsstop command.	The target Datareplicator terminates after terminating import processing on the update information for the batch application.

Definition example

Shown below is an example of the import environment definition for switching the import method during operation. In this example, the target Datareplicator ignores the specification of eventtbl in the import environment definition because the hdsrfctl command is used to control the import processing.

set eventtbl=2

The target Datareplicator permits you to change the import processing method during operation.

To change the import processing method during operation:

1. Execute the hdsrfctl -m spd command at the target system in order to stop import processing.
2. Execute the hdsrfctl -m trn or hdsrfctl -m tbl command at the target system.
3. At the source system, generate an event corresponding to the eventtrn or eventtbl operand in the import environment definition. When the target system detects the event, the import processing method changes.

The target Datareplicator cannot restart selected import groups. If some import groups have terminated due to an SQL error while import processing is underway with the table-based import method, follow the procedure below.

To restart some import groups in error stop status:

1. Execute the hdsrfctl -m immediate or hdsstop -t immediate command at the target system to terminate import processing on the current import groups.
2. Eliminate the cause of the error and execute the hdsrfctl -m tbl or hdsstart command at the target system. The entire import processing starts, with the previous mode inherited.

The source system uses a file transfer program to send a SAM file containing update information to the target system. This SAM file is stored in the target Datareplicator directory specified by the source system's file transfer program.

The target Datareplicator user executes the hdssamqin command to store the update information from the SAM file into the import information queue file. If active, the target system's import processing reads the update information from the import information queue file and updates the target database.