Use the prestartfcmap command to prepare a FlashCopy mapping so that it can be started. This command flushes the cache of any data that is destined for the source volume and forces the cache into the write-through mode until the mapping is started.


prestartfcmap [ -restore ] { fc_map_id | fc_map_name }


(Optional) Specifies the restore flag. This forces the mapping to be prepared even if the target volume is being used as a source volume in another active mapping. An active mapping is in the copying, suspended, or stopping state.
fc_map_id | fc_map_name
(Required) Specifies the name or ID of the mapping to prepare.


This command prepares a single mapping for subsequent starting. The preparation step ensures that any data that resides in the cache for the source volume is first transferred to disk. This step ensures that the copy that is made is consistent with what the operating system expects on the disk.

The restore parameter can be used to force the mapping to be prepared even if the target volume is being used as a source volume of another active mapping. In this case, the mapping is restoring as shown in the lsfcmap view. If the restore parameter is specified when preparing a mapping where the target volume is not the source volume of another active mapping, then the parameter is ignored.

Note: To prepare a FlashCopy mapping that is part of a consistency group, you must use the prestartfcconsistgrp command.

The mapping must be in the idle_or_copied or stopped state before it can be prepared. When the prestartfcmap command is processed, the mapping enters the preparing state. After the preparation is complete, it changes to the prepared state. At this point, the mapping is ready to start.

Attention: This command can take a considerable amount of time to complete. For example, while a volume is in the prepared state, response times might increase.
This command is rejected if the target of the FlashCopy mappings is the secondary volume in a Metro Mirror, Global Mirror, or active-active relationship (so that the FlashCopy target is the remote copy secondary). Remote copy includes Metro Mirror, Global Mirror, and active-active.
Note: If the remote copy is idling or disconnected, even if the FlashCopy and remote copy are pointing to the same volume, the auxiliary volume is not necessarily the secondary volume. In this case, you can start a FlashCopy mapping.
The FlashCopy mapping also fails in the following cases:
  • The remote copy is active.
  • The FlashCopy target (and remote copy primary target) volume is offline. If this occurs, the FlashCopy mapping stops and the target volume remains offline.
Note: Maps that are rc_controlled are not shown in the view when this command is specified.

An invocation example

prestartfcmap 1

The resulting output:

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