Situation: The client has a Server 2008R2 domain controller. He plans to run Azure AD Connect to sync the AD. However, Azure AD Connect has a problem to sync. dcdiag /test:DNS also shows errors.
Troubleshooting: we run ipconfig /all and find this server is mutil-home computers with two NICs. In most cases, this may cause DNS issue. Removing one of NICs fixes the problem.
