The pre-processing and post-processing for a file system is typically the unmounting and remounting of the file system. (For Windows, the processing consists of allocating and cancelling a drive letter.) Pre-processing and post-processing of the replication source volume is performed in order to guarantee the replication source data by disabling access from other processes during execution of synchronous processing and snapshot copy.
If no volume is mounted, the pre-processing and post-processing are not performed.
If the replication source/destination volume is a Logical Unit (disk), pre-processing and post-processing are not performed for the slices included in the Logical Unit (disk). Therefore, the slices included in the Logical Unit (disk) must be unmounted before creating a replica, and the unmounted slices must be mounted after the replica is made.
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.
Command | Copy status | Source/Destination | Preprocessing | Post-processing |
|---|---|---|---|---|
Copy not started, or | Source | X | X | |
Destination | O--*1 | X | ||
Equivalency maintenance | Source | O | O | |
Destination | X | O--*2 | ||
Equivalency maintenance | Source | O | O | |
Destination | X | O--*2 | ||
Replication establishment | Source | X | X | |
Destination | X | X | ||
Copying | Source | X | X | |
Destination | X | X | ||
Copy not started | Source | O | O | |
Destination | O | O |
O : Executed,
X : Not executed
The post-processing for the pre-processing executed in step (*1) is executed in step (*2). In the post-processing in (2), re-mount is performed for the mount point where unmount was performed in the pre-processing in (1).
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
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:
Error code | Usage |
|---|---|
0-99 | Unusable (reserved for AdvancedCopy Manager) |
100-255 | Usable |
Note
AdvancedCopy Manager does not support pre-processing and post-processing of databases.Database pre-processing and post-processing must be executed uniquely before and after (respectively) the execution of the AdvancedCopy Manager command.
