If you use hardware replication like IBM PPRC, then in case of disaster, You 'll present the replicated disks to the remote site.

The correct option is to use Keep Existing Signature, to prevent problem with datastore

1. Log in to the vSphere Client and select the server from the inventory panel.
2. Click the Configuration tab and click Storage in the Hardware panel.
3. Click Add Storage.
4. Select the Disk/LUN storage type and click Next.
5. From the list of LUNs, select the LUN that has a datastore name displayed in the VMFS Label column and click Next.
The name present in the VMFS Label column indicates that the LUN is a copy that contains a copy of an existing VMFS datastore.
6. Under Mount Options, select Keep Existing Signature.
7. In the Ready to Complete page, review the datastore configuration information and click Finish.

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