Error received when attempting to start/restart/flush Authentication Service:
"Entering disconnected state due to VAS error: Preauthentication failed, error code = 13
Could not load caches- Authentication failed, error = Preauthentication failed"
Cause: The unix machine's computer object in active directory has been modified or re-set.
Re-create the UNIX computer's Host Object in Active Directory:
# vastool -u <ADadmin> create host/