Clients externally need to be able to register in DNS for manage-out to work.
You need "something" that separates internal lan from external in order to force the client to connect to DA. Not really sure what "DA server is not communicating with DC not Win 7 client. " means. When all machines are on the internal network, they should
be able to communicate.
For starters, follow Test Lab Guide for 2012 DA available
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