Almost ready to start moving users. All that's left is to change my NAT policy to point our MX record to the Exchange 2010 server and to configure the 2010 OWA virtual directory for legacy redirection. My question is, in the following syuntax:
Set-OWAVirtualDirectory <CAS2010>\OWA* -Exchange2003URL https://legacy.contoso.com/exchange
Is "<CAS2010>\OWA*" the internal name of the 2010 server or the external "mail.mycompany.com"? Thanks.