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If you do not specify the Retain Copy Mode, the copy policies from the mount cluster are refreshed at mount time. When clusters do not agree on MC settings, this issue can result in more copies being made that were not intended because the consistency points can change with each mount. 

DAA often prevents such conditions, but it is still recommended to enable Retain Copy Mode when peers do not have identical MC settings. Existing copies are not removed if they are present. Remove any non-required copies by using the LIBRARY REQUEST REMOVE  command. 

If a virtual volume is modified during a specific mount operation, it is premigrated to back-end tape or cloud (if present) and has all copy policies acknowledged. The virtual volume is transferred to all defined consistency points. 

If no modification occurs while the volume is mounted, the TS7700 does not schedule another copy operation and any current copy of the logical volume on a stacked volume or in the cloud remains active. Furthermore, copies to remote TS7700 clusters are not required if modifications were not made 

## 2.4.13 Logical WORM support and characteristics 

No differences exist between LWORM in multicluster and stand-alone cluster environments. The LWORM behavior for any logical volume is consistent across all clusters in the grid. 

## 2.4.14 Virtual drives 

From a technical perspective, no differences exist between virtual drives in a multi-cluster grid versus a stand-alone cluster. Each cluster has 256 drives per default (see Table 2-1). 

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