SynfinityCLUSTER or PRIMECLUSTER
For replication operation in a clustered system, note the following points that do not apply to regular operation:
If failover occurs while running a replication command, you must secure consistency by using swsrprecoverres (Resource adjustment command) as a recovery measure.
You must perform replication operation on the active system of the cluster service (userApplication) because AdvancedCopy Manager is placed in the cluster service (userApplication) and operates as part of said cluster service (userApplication).
You cannot perform replication from a standby node or another cluster service (userApplication).
SynfinityCLUSTER
Note the following points if a file system has been created on a copy source volume and the file system has been registered as a clustered system resource.
Change the pre-processing and post-processing for replication so that the copy source volume is not unmounted.
Set up a RAW partition on the copy destination volume.
Data cannot be restored from the copy destination volume to the copy source volume using swsrpmake (Replication creation command) during transaction operations. To restore data on the volume, either copy the data using the dd command, or mount the copy destination volume and copy the necessary data. Alternatively, perform the procedure described in "9.1.8.1 Replication during the stoppage of a cluster".
PRIMECLUSTER 4.1A30 or later
Note the following points if a file system has been created on a copy source volume and the file system has been registered as a clustered system resource.
Set up a RAW partition on the copy destination volume.
Follow the procedure below to perform replication.
Switch userApplication to Maintenance mode.
# hvutil -m on userApplication |
Unmount the replication source volume (this is mandatory to replicate a replication source volume in the file system).
If the replication source volume was unmounted, then make sure that the cluster resources of the volume are Offline (wait until the return value of the command is 0):
# hvassert -s <replication_source_volume> <cluster_resource_name> Offline |
Perform replication.
# /opt/FJSVswsrp/bin/swsrpmake <from_volume_name> <to_volume_name> FROM=<from_volume_name> TO=<to_volume_name> swsrpmake completed |
If the replication source volume was unmounted, then mount it back.
Make sure that the cluster resources of the replication source volume are Online (wait until the return value of the command is 0):
# hvassert -s <replication_source_volume> <cluster_resource_name> Online |
Stop Maintenance mode for userApplication.
# hvutil -m off userApplication |
Start synchronization processing.
# /opt/FJSVswsrp/bin/swsrpstartsync <from_volume_name> <to_volume_name> FROM=<from_volume_name> TO=<to_volume_name> swsrpstartsync completed |
Check the equivalency maintenance status.
Switch userApplication to Maintenance mode.
# hvutil -m on userApplication |
Unmount the replication source volume (this is mandatory to replicate a replication source volume in the file system).
If the replication source volume was unmounted, then make sure that its cluster resources are Offline (wait until the return value of the command is 0):
# hvassert -s <replication_source_volume> <cluster_resource_name> Offline |
Perform replication.
# /opt/FJSVswsrp/bin/swsrpmake <from_volume_name> <to_volume_name> FROM=<from_volume_name> TO=<to_volume_name> swsrpmake completed |
If the replication source volume was unmounted, then mount it back.
Make sure that the cluster resources of the replication source volume are Online (wait until the return value of the command is 0):
# hvassert -s <replication_source_volume> <cluster_resource_name> Online |
Stop Maintenance mode for userApplication.
# hvutil -m off userApplication |
Note
In either procedure, if the replication source volume was unmounted, then the pre- and post-processing scripts will not be executed (they are only executed when the transaction or replication source volumes are mounted).
If the applicable parts of the pre- and post-processing scripts are being customized, take this point into account.
The cluster detector detects the status of cluster resources either periodically or asynchronously. Therefore, it may take a few moments for the cluster resource status to be reflected, depending on the system load, and on the timing of mounting/unmounting the replication source volume. This means that the status may not be able to be checked using the hvassert command.
Due to this fact, note the following about the timing of using hvassert to check the cluster resource status:
Once the mounting/unmounting of the file system of a cluster FSystem resource has finished, only use hvassert after the time elapsed is equal to or greater than the cluster resource monitoring interval.
You can specify the maximum time to wait until the cluster reaches the desired status by using hvassert with the -w option:
# hvassert -w <replic_src_vol> <cluster_res_name> Offline|Online <max_wait_time(secs)> |
When using hvassert with the -w option, the system load and cluster resource reflection processing time must also be taken into account.
Due to that, make sure to specify a value that suits the system operating environment, purpose, and requirements.
In PRIMECLUSTER 4.2, the default monitoring interval for the PRIMECLUSTER Fsystem resource is 10 seconds - check the default value for your version.
For details on the hvassert command, refer to the "PRIMECLUSTER Installation and Administration Guide", section "hvassertt(1M)".
VERITAS Cluster Server
For replication in a clustered system, note the following points that do not apply to regular operation:
If failover occurs while running a replication command, you must ensure consistency by using swsrprecoverres (Resource adjustment command) as a recovery measure.
When you use synchronous replication, do not register any destination volumes to a cluster transaction.
You must perform replication on the active system of the service groups because AdvancedCopy Manager is placed in the service groups and operates as a part of it.
You cannot perform replication from a standby node or another service group.
To perform replication, you must unmount original/source volumes beforehand and mount the volumes later for some commands.
If the mount points of original/source volumes have been registered to a cluster transaction, set the mount point resources online or offline from the cluster transaction instead of mounting or unmounting the volumes. Alternatively, modify the unmount and mount processes in the replication pre-processing and post-processing scripts to offline and online processes, respectively.
Moreover, the Volume is immediately placed offline/online for a mount point resource whereas there will be a time delay when mount/unmount is used. Therefore, please add into the pre-processing script, after the statement where the success or failure value of offline/online is returned, the df or sleep command to function until mount/unmount is actually complete.
For details and examples on the types of commands that require the volumes to be unmounted and mounted, and the pre-processing and post-processing scripts, refer to "Appendix C Pre-processing and Post-processing of Replication". For details on the commands used to set resources online and offline, refer to the relevant clustered system manual.
SynfinityCLUSTER or PRIMECLUSTER
When a cluster service (userApplication) to which AdvancedCopy Manager belongs is operating, replication operation is enabled only on the active node. The standby node environment is not ready (to provide necessary resources) for replication operation, thus disabling replication operation. Likewise, if the cluster service (userApplication) has been stopped, the environment is not ready and disables replication operation.
However, only when the cluster service (userApplication) has been stopped is replication operation enabled by temporarily arranging the minimum essentials.
Note
When transactions in scalable operation are handled together, only stop cluster service (userApplications) in scalable operation; do not stop cluster service (userApplications) for Management Server transaction and Managed Server transactions.
Enabling replication operation disks (source volume/destination volume to operate) allows you to perform replication operation in the same way as for regular operations.
If a replication operation disk cannot be enabled, you cannot perform replication operation while a cluster service (userApplications) in scalable operation is stopped.
If any of the following types of shared disks cannot be enabled (i.e., set online or mounted in a system), replication operation is disabled.
Shared disk for AdvancedCopy Manager shared data
Replication operation disks (source volume/destination volume to operate)
The following operations are not allowed in replication operation:
Manipulation for replication operation from a Management Server (host specification with the -h option)
Addition or deletion of an original/replica volume
Inter-server replication without the -m option specified
To execute a display command for replication management to a Management Server transaction that also functions as a Managed Server transaction, you must specify options for the command. For details on the display command for replication management, refer to the "8.4 Replication Management Commands".
Perform replication operation during stoppage of a cluster service (userApplication) by taking the following steps:
Confirm that the cluster service (userApplication) has been stopped on both nodes.
For details on how to stop a userApplication, refer to the SynfinityCLUSTER or PRIMECLUSTER manual.
Log in to the node on which you want to perform replication operation through telnet, for example.
You cannot use the logical IP address. Directly use a node that is operable by using the physical IP address.
Enable the shared disk.
Start (set online) the shared disk.
Mount the shared disk for AdvancedCopy Manager shared data.
When the original volume and replica volume have been mounted as file systems for operation, mount the volumes.
Note
Be sure to enable the shared disk from either node. Do not enable the shared disk from both nodes.
In the environment variable SWSTGNODE, set the logical node name for the relevant task.
Set the environment variable as shown below.
<Execution example>
# SWSTGNODE=logical-node-name # export SWSTGNODE |
Perform replication operation.
You can perform replication operation in the same way as for regular operations for cluster operation.
You can also perform restoration from the replica volume to the original volume.
Release all the shared disks you enabled in Step 3.
Unmount the file systems you mounted.
Stop (set offline) the shared disk.
Start (set online) the cluster service (userApplication).
Start the userApplication, if necessary.
For details on how to start a cluster service (userApplication), refer to the SynfinityCLUSTER or PRIMECLUSTER manual.
VERITAS Cluster Server
When a service group to which AdvancedCopy Manager belongs is operating, replication is enabled only on the active node. The standby node environment is not ready (to provide necessary resources) for replication, and replication is, therefore, disabled. Likewise, if the service group has been stopped, the environment is not ready and disables replication.
However, replication is temporarily enabled when the service group has been stopped.
Note
If any of the following types of shared disks cannot be enabled (i.e., set online or mounted in a system), replication is disabled.
Shared disk for AdvancedCopy Manager shared data
Replication operation disks (source volume/destination volume to operate)
The following operations are not allowed in replication:
Manipulation for replication from a Management Server (host specification with the -h option)
Addition or deletion of an original/replica volume
Inter-server replication without the -m option specified
To execute a display command for replication management to a Management Server transaction that also functions as a Managed Server transaction, you must specify options for the command. For details on the display command for replication management, refer to "8.4 Replication Management Commands".
Perform replication during stoppage of the service group by taking the steps below.
Confirm that the service group has been stopped on both nodes.
For details on how to stop a service group, refer to the VERITAS Cluster Server manual.
Log in (for example, through Telnet) to the node on which you want to perform replication.
You cannot use the logical IP address. Use a node that is operable via the physical IP address.
Enable the shared disk.
Start (set online) the shared disk.
Mount the shared disk for AdvancedCopy Manager shared data.
When the original volume and replica volume have been mounted as file systems for operation, mount the volumes.
Note
Be sure to enable the shared disk from either node. Do not enable the shared disk from both nodes.
In the SWSTGNODE environment variable, set the logical node name for the relevant task.
Set the environment variable as shown below.
<Execution example>
# SWSTGNODE=logical-node-name # export SWSTGNODE |
Perform replication.
You can perform replication in the same way as for regular operations in a cluster environment.
You can also perform restoration from the replica volume to the original volume.
Release all the shared disks you enabled in Step 3.
Unmount the file systems you mounted.
Stop (set offline) the shared disk.
Start (set online) the service group.
Start the service group, if necessary.
For details on how to start a service group, refer to the VERITAS Cluster Server manual.
