Question : Multiple CAS, Multiple Sites

I need help understanding how to configure CAS/Autodiscover in a multple cas server multple site configuration.  I have two mb/hub/cas server in site "A", I have another mb/hub/cas in site "B", all servers are apart of the same DAG.  The two servers in site "A" are behind a hardware load balancer and setup in a CAS Array, the single server in site "B" is obviously not in a CAS Array.  How do I configure autodiscover so that in the event site "Site A" is down site that "Site B" will automatically failover CAS services and provide mapi/owa, etc......?  

Also:
In my DR site I’m trying to connect to the exchange server from a client in the same site, but I’m unable to get connected to exchange 2010.  Do I need to configure anything on CAS such as the database name?  I know this is done on the CAS Array, but maybe it needs to be done on a standalone CAS as well.

The firewall between the sites are completely wide open.

Answer : Multiple CAS, Multiple Sites

you will need to configure the rpclientaccessserver attribute on the database so clients can connect to the correct CAS