Your company has a hybrid deployment of Office 365 that uses single sign-on. The network contains a server named Server1 that has the Active Directory Federation Services (AD FS) 2.0 server role insta

Your company has a hybrid deployment of Office 365 that uses single sign-on. The network contains a server named Server1 that has the Active Directory Federation Services (AD FS) 2.0 server role installed and a server named TMG1 that has Microsoft Forefront Threat Management Gateway (TMG) installed. All access from the Internet to the internal network passes through TMG1. You deploy a second AD FS server named Server2 and configure Network Load Balancing (NLB). You shut down Server1 for routine maintenance. Users on the Internet report that they cannot log on to Office 365 by using their Active Directory credentials. Users on the internal network report that they can log on to Office 365 by using their Active Directory credentials. You need to ensure that all of the users can log on to Office 365 if Serverl is unavailable. What should you do?