ETERNUS SF AdvancedCopy Manager V15.3 Operation Guide

C.2.1 Pre-processing and post-processing for a file system

Pre-processing and post-processing for a replication source volume are performed to guarantee a replication destination volume.
Pre-processing and post-processing for a replication destination volume is performed to prevent other processes from accessing to the volume during synchronization processing or snapshot copy.

If the replication source and destination volumes are partitions, it is assumed that a file system has been constructed on the volumes and the following pre-processing and post-processing are performed.

Table C.1 When the replication source/destination volume are partitions

Target	Type	Details
Replication source volume	Pre-processing	Default operation: The file system buffer of replication source volume is flushed. When the -Xflush option is not specified and BufferFlushOnly is set to off: The replication source volume is locked. When the -f option is specified: No processing is performed (i.e., the source pre-processing script is not executed).
	Post-processing	Default operation: No processing is performed. When the -Xflush option is not specified: The replication source volume is unlocked. When the -f option is specified: No processing is performed (i.e., the source post-processing script is not executed).
Replication destination volume	Pre-processing	Default operation: The replication destination volume is locked. When the -t option is specified: No processing is performed (i.e., the destination pre-processing script is not executed).
	Post-processing	Default operation: The replication destination volume is unlocked. When the -t option is specified: No processing is performed (i.e., the destination post-processing script is not executed).

If the replication source volume and the replication destination volume are Logical Units (disks), the following pre-processing and post-processing are performed.

Table C.2 When the replication source/destination volume are Logical Units (disks)

Target	Type	Details
Replication source volume	Pre-processing	Default operation: The file system buffer of the partition included in the Logical Unit (disk) is flushed. When the -Xflush option is not specified and BufferFlushOnly is set to off: The partition included in the Logical Unit (disk) is locked. When the -f option is specified: No processing is performed (i.e., the source pre-processing script is not executed).
	Post-processing	Default operation: No processing is performed. When the -Xflush option is not specified: The partition included in the Logical Unit (disk) is unlocked. When the -f option is specified: No processing is performed (i.e., the source post-processing script is not executed).
Replication destination volume	Pre-processing	Default operation: The partition included in the Logical Unit (disk) is unlocked. The drive character or mount point assignment of the partition included in the Logical Unit (disk) is released. The partition included in the Logical Unit (disk) is deleted. When the -t option is specified: No processing is performed (i.e., the destination pre-processing script is not executed).
	Post-processing	Default operation: The operating system is notified that Logical Unit (disk) management information (partition table, etc.) has been updated. If "C.2.6 Drive character mapping file" contains settings for the copy destination disk, the following processing is executed: The system waits until the status of the partition in the Logical Unit (disk) allows assignment of a drive character or mount point. A drive character or mount point is assigned in accordance with the drive character mapping file. When the -t option is specified: No processing is performed (i.e., the destination post-processing script is not executed).

The implementation status of the pre-processing and post-processing for a file system is shown below.
This table shows whether pre-processing and post-processing are performed depending on the command type. It also shows the copy status at the time of the command execution.

Table C.3 Pre-processing and post-processing for a file system

Command	Copy status	Source/Destination	Pre-processing	Post-processing
swsrpstartsync (Synchronous processing start command)	Copy not started, or replication establishment	Source	X	X
		Destination	O--*1	H--*2
swsrpmake (Replication creation command)	Equivalency maintenance	Source	O	O
		Destination	H--*1	O--*2
swsrpcancel (Replication cancellation command)	Equivalency maintenance	Source	O	O
		Destination	H--*1	O--*2
	Replication establishment	Source	X	X
		Destination	X	X
	Copying	Source	X	X
		Destination	X	H--*2
swsrpmake (Replication creation command)	Copy not started	Source	O	O
		Destination	O	O

O: Executed
H: Indicates execution when the destination volume is a shared volume in a clustered system (note, however, that no call is made to the destination post-processing script).
X: Not executed

The post-processing for the pre-processing executed in step (*1) is executed in step (*2).

The pre-processing and post-processing for a file system can be customized. The processing is started in accordance with the table above when a replication management command is executed. For replication between servers, these scripts are executed by remote execution using TCP/IP in the pre-processing and post-processing of a volume that is not connected.

The operation image before and after processing is shown in the following figure.

Figure C.1 Synchronized replication processing (flushing the file system buffer of replication source volume)

Figure C.2 Synchronized replication processing (locking the replication source volume)

If processing other than the standard pre-processing and post-processing is required in the pre-processing and post-processing, customize the scripts.

When customizing a script, strictly observe the following rules regarding error codes:

Table C.4 Error code rules

Error code	Usage
0-99	Unusable (reserved for AdvancedCopy Manager)
100-255	Usable

Note

AdvancedCopy Manager provides pre-processing and post-processing for Oracle, SQL Server, Exchange and Hyper-V applications. In case of using any other application than these, if needed, pre-processing and post-processing must be executed uniquely before and after (respectively) the execution of the AdvancedCopy Manager command.