Exadata monitoring with Enterprise Manager 12c

Hi,

I've installed Enterprise Manager 12c on a standalone server to monitor the 1/4 Exadata X2-8. 

EM server OS:OEL 5.7, repos DB: 11.2.0.1

 The configuration status:

1.add hosts as target : 2 computer nodes added.all the OS info can be showed on EM dashbord. 

2.add none-hosts target :  exadata machine ,all the other componets (storage cell, KVM,PDU,IB Switch ,Cisco Switch) are discovered automaticly,and input the root with password finished

3.add cluster system : finished

4. add database,listener,ASM: finished

but the 3 storage cell status is unavailable, and can not fetche any OS data or disk data from the storage cells.  

I'm not sure if I need to push an agent to each storage cell, whic can be done with adding 3 storage cells as linux 64 hosts .