Hello,
Weclome to VMware communities!!!.
I believe partition table might be missing.
On ESXi Shell, please verify if it has valid partition table and let me know the results.
1. Identify the naa.id of the datastore.
You can get this info by
~ # esxcfg-scsidevs -m
naa.6006016017702500acddb9377e7ce211:1 /vmfs/devices/disks/naa.6006016017702500acddb9377e7ce211:1 5126a55e-1ff4d6be-88f7-001e4ffc1b71 0 Shared
In this Example "Shared' Datastore points to /vmfs/devices/disks/naa.6006016017702500acddb9377e7ce211:1, so check the partition table on it.
if esxcfg-scsidevs -m, doesnt give any info then try
~ # esxcfg-scsidevs -c and get the info.
~ # partedUtil getptbl /vmfs/devices/disks/naa.6006016017702500acddb9377e7ce211
gpt
13054 255 63 209715200
1 2048 209715166 AA31E02A400F11DB9590000C2911D1B8 vmfs 0