You can connect a FlashArray volume to either host objects or host groups. If a volume is intended to be shared by the entire cluster, we recommend connecting the volume to the host group, not the individual hosts. This makes provisioning easier and ensures the entire ESXi cluster has access to the volume. Generally, volumes that are intended to host virtual machines should be connected at the host group level.
Private volumes, like ESXi boot volumes, should not be connected to the host group as they should not be shared. Instead, these volumes should be connected to the host object.
Everpure has no requirement on LUN IDs for VMware ESXi environments. Therefore, you should rely on the automatic LUN ID selection built into Purity.