NetApp and VMware vSphere Storage Best Practices

10.7 DATASTORE CONFIGURATION WITH MULTISWITCH TRUNKING
In addition to properly configuring the vSwitches, network adapters, and IP addresses, using multiple
physical paths simultaneously on an IP storage network requires connecting to multiple datastores, making
each connection to a different IP address.
In addition to configuring the ESX Server interfaces as shown in the examples, the NetApp storage
controller has been configured with an IP address on each of the subnets used to access datastores. This is
accomplished by the use of multiple teamed adapters, each with its own IP address or, in some network
configurations, by assigning IP address aliases to the teamed adapters, allowing those adapters to
communicate on all the required subnets.
When connecting a datastore to the ESX Servers, the administrator configures the connection to use one of
the IP addresses assigned to the NetApp storage controller. When using NFS datastores, this is
accomplished by specifying the IP address when mounting the datastore.
The figure below show an overview of storage traffic flow when using multiple ESX Servers and multiple
datastores. Note with iSCSI this design is represented as multiple IP paths to a single SCSI target, only one
IP path is active per datastore, however each ESX/ESXi host may use a different active IP path. This
behavior can be changed to send I/O traffic over multiple paths by enabling the Round Robin multipathing
plug-in (as covered in section 4.5). Regarding NFS datastores each datastore should be connected only
once from each ESX/ESXi server, and using the same netapp target IP address on each ESX/ESXi server.
Figure 41) Datastore connections with cross-stack Etherchannel.
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