Considerations for using SnapMirror for transition
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You can create data copy schedules and customize the SnapMirror data transfers for transition operations without affecting the existing 7-Mode to 7-Mode SnapMirror or SnapVault operations.
Maximum number of concurrent SnapMirror transfers
During transition, the maximum number of concurrent SnapMirror transfers supported on the 7-Mode and ONTAP systems depend on the number of volume SnapMirror replication operations allowed for a specific storage system model.
For information about the maximum number of concurrent volume SnapMirror transfers for your system model, see the Data ONTAP Data Protection Online Backup and Recovery Guide for 7-Mode.
Data copy schedules
The number of concurrent SnapMirror transfers that the tool uses for running the SnapMirror operations (baseline, update, or resynchronization) is based on the schedules you configure while creating the project.
If different projects are transitioning volumes from the same 7-Mode controller, you must ensure that the data copy schedules do not overlap across different projects.
You can ensure that your existing backup and disaster recovery (DR) operations are not impacted by the 7-Mode Transition Tool transition operations in the following ways:
You should create SnapMirror data copy schedules for a project such that it does not overlap with the existing 7-Mode SnapMirror or SnapVault schedules.
You should configure the number of concurrent SnapMirror transfers to run in such a way that the existing 7-Mode SnapMirror or SnapVault schedules do not fail.
You can also release some transfers by editing the active schedule and modifying the maximum number of concurrent volume SnapMirror transfers to zero.
You must ensure that the number of concurrent SnapMirror transfers and the throttle configured for the operations (precutover, cutover, and on-demand update) are available on the 7-Mode storage system for the entire duration of the operation.
The cutover operation fails if the final incremental update operation fails even for one of the volumes in the project.
For secondary projects, after cutover, the incremental SnapMirror updates for the SnapMirror relationship between the 7-Mode primary volumes and the ONTAP secondary volume is based on the 7-Mode to 7-Mode SnapMirror relationship schedule.
You must ensure that there are sufficient concurrent SnapMirror transfers available on the 7-Mode primary controller for these updates to occur.
Using multiple paths for transition
You can specify two paths for transition by using a data copy IP address and a multipath IP address. However, both paths can be used only for load-balancing, not for failover.