I would like to manage Celerra NS20 and Clariion CX600 by ECC 6.0.

So the simple answer to your question is "yes". You can monitor and manage both CLARiiON and Celerra from ControlCenter. The more complicated answer is "you have to confirm the FLARE code levels and firmware on the arrays against the ControlCenter Support Matrix documentation"

Now as for your second question on what you need to manage them... that also depends on what you want to do:
* First check the Support matirx doc mentioned above for agent requirements
* For Celerra you will need the Storage Agent for NAS license. This ofers discovery and monitoring, but not management
* For CLARiiON you will need the Storage Agent for CLARiiON licence. This includes "everything" except for LUN Masking
* For LUN Masking on the CLARiiON you will need the SAN Manager licence
* For reporting you will need to StorageScope licence
There is a ControlCenter Management Package for CLARiiON which includes licensing for CLARiiON, StorageScope, SAN Manager, and Performance Manager or a package for NAS which replaces the CLARiiON licence with the NAS licence.

That should get you started. However, you will probably find that while ControlCenter is great for monitoring, alerting, and reporting on CLARiiON... it is not as good for provisioning (in my experience). You may find that you want to keep provisioning the CLARiiON directly in Navisphere, and just rely on CC for what it is really good at.