Explanation/Reference:
Explanation : By default, the VMware NMP supports the following PSPs:
VMW_PSP_MRU
The host selects the path that it used most recently. When the path becomes unavailable, the host selects an alternative path. The host does not revert back to the original path when that path becomes available again. There is no preferred path setting with the MRU policy. MRU is the default policy for most active- passive storage devices.
Displayed in the vSphere Client as the Most Recently Used (VMware) path selection policy.
VMW_PSP_FIXED
The host uses the designated preferred path, if it has been configured. Otherwise, it selects the first working path discovered at system boot time. If you want the host to use a particular preferred path, specify it manually. Fixed is the default policy for most active-active storage devices.
Note
If the host uses a default preferred path and the path's status turns to Dead, a new path is selected as preferred. However, if you explicitly designate the preferred path, it will remain preferred even when it becomes inaccessible.
Reference: https://pubs.vmware.com/vsphere-51/index.jsp?topic=%2Fcom.vmware.vsphere.storage.doc%
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