Skip to main content
ONTAP MetroCluster

Requirements for a MetroCluster configuration with array LUNs

Contributors netapp-driley netapp-ahibbard netapp-folivia netapp-thomi

The ONTAP systems, storage arrays, and FC switches used in MetroCluster configurations must meet the requirements for such types of configurations. In addition, you must also consider the SyncMirror requirements for MetroCluster configurations with array LUNs.

Requirements for ONTAP systems

  • The ONTAP systems must be identified as supported for MetroCluster configurations.

    In the NetApp Interoperability Matrix Tool (IMT), you can use the Storage Solution field to select your MetroCluster solution. You use the Component Explorer to select the components and ONTAP version to refine your search. You can click Show Results to display the list of supported configurations that match the criteria.

    Note You must refer to the alert details associated with any configuration that you select in the Interoperability Matrix.
  • All the ONTAP systems in a MetroCluster configuration must be of the same model.

  • FC-VI adapters must be installed in the appropriate slots for each ONTAP system, depending on the model.

Requirements for storage arrays

Requirements for FC switches

  • The switches and switch firmware must be identified as supported for MetroCluster configurations.

  • Each fabric must have two FC switches.

  • Each ONTAP system must be connected to storage using redundant components so that there is redundancy in case of device and path failures.

  • AFF A700, FAS9000, AFF A900, and FAS9500 storage systems support up to eight ISLs per fabric. Other storage system models support up to four ISLs per fabric.

The switches must use the MetroCluster basic switch configuration, ISL settings, and FC-VI configurations.

SyncMirror requirements

  • SyncMirror is required for a MetroCluster configuration.

  • Two separate storage arrays, one at each site, are required for the mirrored storage.

  • Two sets of array LUNs are required.

    One set is required for the aggregate on the local storage array (pool0) and another set is required at the remote storage array for the mirror of the aggregate (the other plex of the aggregate, pool1).

    The array LUNs must be of the same size for mirroring the aggregate.

  • Unmirrored aggregates are also supported in the MetroCluster configuration.

    They are not protected in the event of a site disaster.

Note It's recommended you maintain at least 20% free space for mirrored aggregates for optimal storage performance and availability. Although the recommendation is 10% for non-mirrored aggregates, the additional 10% of space may be used by the filesystem to absorb incremental changes. Incremental changes increase space utilization for mirrored aggregates due to ONTAP's copy-on-write Snapshot-based architecture. Failure to adhere to these best practices may have a negative impact on performance.