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VMware has become aware of an issue where clusters can enter an inconsistent state when placed into cluster maintenance mode using the vSphere Storage Appliance Manager. This inconsistency can lead to virtual machines becoming inaccessible.
VMware recommends that you do not use the Cluster Maintenance functions in the VSA Manager GUI to take a VSA 1.0 cluster offline. Instead, please follow the instructions in KB: Using the vSA 1.0 Manager GUI to enter cluster maintenance mode can result in clusters entering an inconsistent state (2033400).