Guidelines for implementing a MetroCluster configuration with disks and array LUNs

When planning your MetroCluster configuration for use with disks and array LUNs, you need to follow the guidelines for setting up a MetroCluster configuration for each type of storage, plus the additional guidelines for setting up a MetroCluster configuration with both types of storage.

The basic requirements for using disks and array LUNs in a MetroCluster configuration are the same whether you are using just one type of storage or both. Likewise, installation, configuration, and testing of each type of storage is the same as if you were using just one type of storage.

However, there are additional guidelines to consider if you are using both disks and array LUNs in your MetroCluster configuration.

Consider the information in the following table when planning your configuration:

Consideration Guideline
Order of setting up access to the storage You can set up access to either type of storage first. You should complete all setup for that type of storage and verify that it is set up correctly before setting up the other type of storage.
Root volume location
  • If you are setting up a new MetroCluster deployment with both disks and array LUNs, it is recommended that you create the root volume on native disks.
  • If you are adding native disks to an existing MetroCluster configuration that uses array LUNs, the root volume can remain on an array LUN.
FC initiator port usage You need to use different FC initiator ports to connect to a FibreBridge 6500N bridge than you use to connect to the switches that connect to the storage arrays.

When FibreBridge 6500N bridges are used in a MetroCluster configuration with disks and array LUNs, four FC connections are required for native disk shelves connected through the FibreBridge 6500N and four FC connections are required for the FC connections to target ports on the storage arrays. Therefore, a minimum of eight FC initiator ports are required for a Data ONTAP system to connect to both native disks and array LUNs. Not all platforms can support eight FC initiator ports. See the Hardware Universe at hwu.netapp.com to determine whether your platform can support eight FC initiator ports.

Switches and switch port usage in MetroCluster configurations using FibreBridge 6500N bridges For stretch MetroCluster configurations, only direct connection to a FibreBridge 6500N bridge is supported. Switches are used to connect to the storage arrays.
For fabric-attached MetroCluster configurations, the rules for switches are as follows:
  • The same switches are used to connect to the storage arrays and the FibreBridge 6500N bridges.
  • The switch ports used to connect to a FibreBridge 6500N bridge must be different from the switch ports used to connect to a storage array.
Reverting

(Transitioning a storage system to a Data ONTAP release in an earlier family)

You cannot revert a system set up with a mixed disk and array LUN MetroCluster configuration to a release prior to Data ONTAP 8.2 because a mixed disk and array LUN MetroCluster configuration is not supported prior to Data ONTAP 8.2.