When your datastore is inaccessible, it means you lost your path. so you can follow the below steps:
- Check the physical connectivity of your ESXi, Storage, and every component between your ESXi hosts and storage
- If you are using SCSI-based storage, make sure to configure protocol endpoints on the storage side, or if you created endpoints, double-check the configuration
- If you are using SAN-based storage, check your SAN switches for any misconfiguration such as zoning and zone-sets
- Check volume status in your storage, if they become offline, your datastores will be inaccessible. double-check LUN masking in your storage.
- If you are using local storage, check your local RAID controller, drivers, and firmware.
