Storage Array Type Plug-ins (SATPs) are responsible for array-specific operations. The SATPs are submodules of the VMware NMP.
ESXi offers an SATP for every type of array that VMware supports. ESXi also provides default SATPs that support non-specific active-active, active-passive, ALUA, and local devices.
Each SATP accommodates special characteristics of a certain class of storage arrays. The SATP can perform the array-specific operations required to detect path state and to activate an inactive path. As a result, the NMP module itself can work with multiple storage arrays without having to be aware of the storage device specifics.
Generally, the NMP determines which SATP to use for a specific storage device and associates the SATP with the physical paths for that storage device. The SATP implements the tasks that include the following:
- Monitors the health of each physical path.
- Reports changes in the state of each physical path.
- Performs array-specific actions necessary for storage fail-over. For example, for active-passive devices, it can activate passive paths.
For more information, see the VMware Compatibility Guide and the vSphere Command-Line Interface Reference documentation.