ESX and Netapp LUN Multipathing Configurations

by julio on

The screen shot below represents an important setting for path management. The text is self explanatory when it comes to understanding the difference between Fixed and MRU. For NetApp controllers configured as they are, it is recommended to set this as fixed. As stated, the preferred path will be used when available.

Path Selection

When necessary, another path can be selected to be the preferred path. The screen shot below illustrates how this is done. Notice that an administrator can enable or disable a path as well.

Path State

Paths for a given LUN can be viewed as shown within the screen capture below.

Manage Path

The below drawing is a graphical representation of how multipathing should be configured on each ESX host. It also clarifies how the ESX host sees and displays the LUNs. We can also see how the VIF represents an iSCSI target. Through both VIFs (iSCSI targets 7 and each LUN can be seen. The red lines below represent the active paths. The inactive paths are not shown here as they would clutter the drawing. However, each target can access each LUN equally. Therefore, altering the preferred paths on an “every other LUN” basis will ensure balanced access across both NICs in the team on each host.