Cabling guidelines for a MetroCluster configuration with array LUNs

There are a number of cabling guidelines that you need to review before connecting the devices in a MetroCluster configuration with array LUNs.

Cabling guidelines for a dual-enclosure HA pair with multiple controllers in the same enclosure

Some platforms, for example, 31xx systems, support two controllers in the same enclosure. For a MetroCluster configuration, you must have two such systems. You configure the two systems into a pair of MetroCluster configurations by connecting the FC-VI adapter between the two top controllers and then connecting the FC-VI adapter between the bottom controllers.

In such a configuration, the internal InfiniBand connections between the controllers in the same enclosure are automatically deactivated. Therefore, the two controllers in the enclosure are no longer in an HA pair with each other. Each controller is connected through FC-VI connections to another controller of the same type, so the four controllers form two independent MetroCluster configurations.

Cabling guidelines for partner-to-partner connections

The cabling for the MetroCluster partners is different on each node of the HA pair. Use the following guidelines to plan your cabling for partner-to-partner connections.

  • Each node in the HA pair must have a different name so that you can distinguish them.
  • One node needs to be identified as being in Site A and the other as being in Site B.

    For example, the local node could be System 1, Site A, and the remote node could be System 2, Site B.

  • Each port on the node must be connected to the same fabric.

    For example, if Port A of the FC-VI adapter on the local node is connected to Switch 2 and Port A of the FC-VI adapter on the remote node is connected to Switch 4, then Switch 2 and Switch 4 must be connected by the ISL, thereby connecting the nodes to the same fabric.

Cabling guidelines for Data ONTAP system-to-switch connections

  • FC ports on the same channel controller chip cannot be connected to the same switch.

    One port must be connected to one switch and the other port must be connected to the other switch. For example, if onboard port 0a is connected to Switch 3, you cannot connect onboard port 0b to Switch 3; port 0b must be connected to Switch 4.

    Note: Connecting both onboard ports of the pair to the same switch port number can simplify cabling and management of the MetroCluster configuration. For example, if port 0a is connected to Port 1, Switch 1, connect port 0b to Port 1, Switch 2.
  • All switches within a fabric must be the same switch model and have the same number of licensed ports.

Cabling guidelines for Inter-Switch connections

You can connect an Inter-Switch Link (ISL) to any available switch port.

Cabling guidelines for Data ONTAP system-to-storage array connections

Cabling between the Data ONTAP systems and the storage arrays must be redundant and conform to the required number of paths (two).