Present the LUN to all the ESXi hosts in the cluster, this is imperative to ensure virtual machine mobility. In a cluster, it's quite typical for a virtual machine to restart or migrate on other hosts, the LUN can be continuously accessed by the virtual machine.
Needless to state, this is a prerequisite for features such as vMotion and HA with Distributed Resource Scheduler (DRS) so they work on the virtual machine in question.