User Site Sync Only Syncing on the Master Site

Thanks, I am trying to sync the master with one subsite, however then I put in the master key and link I get one of two things, it times out or "master site cannot be reached". But when I go back to the master site it shows the subsite and says the sync was successful, but it did not sync the users. I hope I don't have some DNS issues.
Thanks
Ty