Stretch MetroCluster configurations have asymmetrical and active/passive variations.
The following list describes some common configuration variations that are supported for stretch MetroCluster configurations:
Asymmetrical mirroring
You can add storage to one or both nodes that is not mirrored by the other node.
You must mirror the root volumes to enable successful takeover.
Active/passive MetroCluster configurations
In this configuration, the remote (passive) node does not serve data unless it has taken over for the local (active) node. Mirroring the passive node’s root volume is optional. However, both nodes must have all licenses for a MetroCluster configuration installed so that remote takeover is possible.