By design, it is not possible to have multiple Azure AD connect servers sync the same directory data to the same Azure AD tenant. However, Azure AD Connect supports maintaining a second server in staging mode. This is ideal for high availability. A server in staging mode reads data from all connected directories but will not sync it to the Azure AD tenant. It runs sync jobs as a normal Azure AD connect server, so in the case of a disaster, it already has the latest data. In the event of primary server failure, using the Azure AD Connect wizard, we can fail over to the staging server. This method can be used to replace the existing AD connect server. We can make all the relevant changes in staging mode, and when everything is ready, we can fail over to the newly implemented server. Maintaining multiple staging servers in an infrastructure is also supported.