To avoid problems in vCenter 7 installation, use a public NTP server, e.g. (time.google.com) when prompted for NTP. Without using this setting, the services will fail to start, and the deployment will fail at 67% or more in the starting services progress. Even if the deployment succeeds if the appliance restarts, the services will fail to start, and “No healthy uplink” appears forever.
Depending on the time synchronization of the virtual infrastructure may cause the deployment to fail, or the HTLM5 vSphere Web Client error “No healthy upstream”, delayed startup, or even failed startup of services.
vCenter deployment and vSphere Web Client are very sensitive and complicated to the time synchronization. Once we used a Public NTP server – during installation -(time.google.com), everything ran smoothly, vSphere Web Client started on time. Please read this topic in VMware documents “Synchronizing Clocks on the vSphere Network.
In vCenter 7 is mandatory to use reliable clock synchronization.