Straight mapping is nothing but having the controller ownership of LUN and storage ports aligned. For example if you have a LUN for which CTL-1 is owner, then while doing a straight mapping, you need to map it to those storage ports which are owned by CTL-1. That is when the performance will be optimum. In case of cross mapping (mapping a LUN owned by CTL-1 to a storage port which is not owned by CTL-1) performance gets affected.
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Chayan Sarkar
Hardware Test Engineer - Senior
Hitachi Vantara
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