Issue:
After I configured The managed meta data service app on the host farm and then connected to the remote service from farm 2 I received the error below when trying to access the term store from a site hosted on the remote farm
The Managed Metadata Service or Connection is currently not available. The Application Pool or Managed Metadata Web Service may not have been started. Please Contact your Administrator.
Resolution:
The problem ended up being that the remote farm did not have any permissions defined on the host farms Managed Meta Data Service Application. To fix you go to the host farm Managed Meta Data Service Application, and then properties, you then add the remote farms application pool account for the web app the site you are using is on into the permissions on the managed meta data sa and select the term store permissions needed. After this you can refresh the page on the remote farm and the term store will be accessible.
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