This section provides general notes on backup and replication.
The following devices must not be backed up or replicated:
The device on which the system is stored
The device on which AdvancedCopy Manager has been installed
The device on which the management list of AdvancedCopy Manager resides
If performing replication between servers that use the new device file names supported by HP-UX11iv3 or later (/dev/disk/diskN), the AdvancedCopy Manager on the other server must be version 13.4 or later.
Data in transaction volume | Maintenance of data integrity | Operation |
|---|---|---|
File system | An AdvancedCopy Manager command unmounts the file system to maintain the integrity. | Refer to "Appendix A Pre-processing and Post-processing of Backup and Restoration" and "Appendix C Pre-processing and Post-processing of Replication". |
Other than the above | The data integrity must be maintained in operations. | Take appropriate action, such as stopping transactions during execution of backup or replication. |
Before starting either the backup or replication operation, "3.4.4 Fetching device information on a Managed Server" that is managed by all Managed Servers using the Web Console. The time taken to complete this operation is proportional to the total number of devices defined on the selected Managed Servers. If many devices are involved, perform this operation while the CPU or I/O load on the system is low.
As a guide, about 0.5 seconds are required per device (i.e., disk) when there is no load on the system.
When the device has a multipath configuration, a path switch is not carried out automatically, even if one of the two paths is blocked.
When one of the two paths is blocked, please perform the backup or replication again after taking the following steps:
Execute the following command on an available device to switch the path:
/usr/sbin/pvchange -s /dev/dsk/c*t*d* |
Be careful, as the system will stop if the commands are executed on a failed device
Execute the backup or replication command again.
Before backup/restoration or replication of a volume that can be mounted from multiple servers, unmount and cancel any pending mount on the other servers.
For disks that need not be mounted from other servers, prevent multiple servers from detecting or accessing the same logical disk by setting up hardware, such as devices in the ETERNUS Disk storage system and Fibre Channel switches, accordingly.
For a copy operation targeted at a file system, unmount the relevant volume to prevent data access and maintain the data integrity.
If backup/restoration and replication are performed without unmounting the volume, an error occurs since a volume in use cannot be unmounted.
Note the following about processing where unmounting is enabled:
Another application is not using the volume. If another application is using it, suspend the application temporarily.
Users are not using the volume. If users are using it, prohibit them from using it temporarily.
Another volume is not mounted on the volume. If it is mounted, unmount it temporarily.
The volume is not shared with NFS sharing. If it is shared, unshare it temporarily.
Unmounting is required only during command execution. Normal operations can be resumed after command execution.
Copies can be made between different operating systems by using replication operations.
Use the following combinations to execute copy between different operating systems:
Copy source | Copy destination | |
|---|---|---|
slices | Logical Unit (disk) | |
slices | A | N/A |
Logical Unit (disk) | A | N/A |
(A=Available, N/A=Not Available)
Do not create a file system on a copy destination volume (slice).
When replication occurs between servers, the -m option can be specified in the following commands in order to avoid communication processing to non-operating servers:
When the -m option is specified, any one of the following conditions must apply in order to ensure that problems do not arise as a result of not performing volume pre-processing and post-processing at the non-operating server:
The non-operating server has been shut down.
Manual pre-processing and post-processing is performed for the volumes on the non-operating server.
The target volume is a RAW device (Oracle, etc., that does not need pre-processing and post-processing), rather than a file system.
When you execute swsrpstartsync (Synchronous processing start command) with the -t option, volume lock fails with swsrpmake (Replication creation command) and the swsrp3607 message may be output.
If you execute swsrpstartsync (Synchronous processing start command) with the -t option to perform independent pre-processing, check whether the pre-processing has properly been done.
If you determine that pre-processing and post-processing for replication destination volume is not needed and execute swsrpstartsync (Synchronous processing start command) with the -t option, execute swsrpmake (Replication creation command) with the -t option.
The Advanced Copy processing is performed by the ETERNUS Disk storage system. Therefore, direct enquiries concerning copy processing performance to the support department for the ETERNUS Disk storage system.
When a copy destination is a volume group and a restart is performed while executing the synchronous processing (EC/REC), the volume will become inactive. When the copy destination becomes inactive while the synchronous processing is being executed, it cannot be activated again. Moreover, the operation such as stopping the synchronous processing cannot be executed. If it is deactivated by mistake, the synchronous processing must be stopped forcibly using ETERNUS Web GUI and then the copy destination volume is activated.
