In vSAN Original Storage Architecture, a disk group consists of one flash cache device and one or more capacity devices. The cache device is a required component of the disk group, so a failed cache device cannot be replaced as an isolated drive while preserving the same disk group. The supported operational approach is to remove the affected disk group, physically replace the failed cache device, verify that ESX detects the new device, and then manually recreate the disk group using the replacement cache device and the appropriate capacity devices. The scenario states that vSAN has already completed resynchronization and that all objects are healthy and compliant, so removing the failed disk group no longer risks object noncompliance. Selecting Full Data Migration on a failed cache device is not the correct workflow because the cache failure affects the entire disk group. Simply inserting a replacement drive does not cause vSAN OSA to automatically rebuild the disk group. Reference topics: vSAN OSA Disk Groups, Replace a Cache Device, Remove Disk Group, Recreate Disk Group.