Using multiple LUN groups enables you to partition the load over connections. This configuration is supported for most storage arrays. See the Interoperability Matrix to confirm that this configuration is supported with your storage array.
The following illustration shows how one FC initiator port pair (0c and 0f) on the Data ONTAP system accesses one LUN group over one storage array port pair, and a second FC initiator port pair (0a and 0h) accesses a second LUN group on the same storage array over a different storage array port pair.
This multiple LUN group configuration enables you to spread the I/O across the RAID groups (parity groups) on the storage array. You set up your configuration so that different FC initiator port pairs access different groups of LUNs on the storage array. The Data ONTAP system sees any given array LUN over only two paths because a given LDEV (logical device) is mapped to only two redundant ports on the storage array. Each LUN group is accessed through a different target port pair.
Each LDEV is identified externally by a LUN ID. The LDEV must be mapped to the same LUN ID on all storage array ports over which it will be visible to Data ONTAP systems.
The following table summarizes the zoning for this example. Single-initiator zoning is the recommended zoning strategy.
Zone | FC initiator port on the Data ONTAP system | Storage array | |
---|---|---|---|
Switch 1 | |||
z1 | Port 0a | Controller 1 Port B | |
z2 | Port 0c | Controller 1 Port A | |
Switch 2 | |||
z3 | Port 0f | Controller 2 Port A | |
z4 | Port 0h | Controller 2 Port B |
See the Interoperability Matrix to determine whether multiple array LUN groups are supported for your storage array.