Differences between the ONTAP MetroCluster configurations

The various MetroCluster configurations have key differences in the required components.

In all configurations, each of the two MetroCluster sites is configured as an ONTAP cluster. In a two-node MetroCluster configuration, each node is configured as a single-node cluster.

Feature IP configurations Fabric-attached configurations Stretch configurations
Four- or eight-node Two-node Two-node bridge-attached Two-node direct-attached
Number of controllers Four Four or eight Two Two Two
Uses an FC switch storage fabric No Yes Yes No No
Uses an IP switch storage fabric Yes No No No No
Uses FC-to-SAS bridges No Yes Yes Yes No
Uses direct-attached SAS storage Yes (local attached only) No No No Yes
Supports ADP Yes (starting in ONTAP 9.4) No No No No
Supports local HA Yes Yes No No No
Supports automatic switchover No Yes Yes Yes Yes
Supports unmirrored aggregates Yes (starting in ONTAP 9.8) Yes Yes Yes Yes
Supports array LUNs No Yes Yes Yes Yes