vCenter upgrade failed at the end of stage one with error "The installer is unable to connect to the vCenter Appliance Management Interface"

Products

• VMware vCenter Server 7.0

Issue/Introduction

• vCenter upgrade is performed from one Windows workstation.
• upgrade failed at the end of stage one with error:
  
  The installer is unable to connect to the vCenter Appliance Management Interface.
Installer log files are located at C:\Users\<user name>\AppData\Local\Temp\vcsaUiInstaller
  
  
• Windows workstation is unable to connect to the newly deployed vCenter VAMI page (port 5480) with error "ERR_CONNECTION_TIMED_OUT".
• You were able to connect to the previous vCenter VAMI page.

Environment

VMware vCenter Server 7.0

Cause

Port 5480 is blocked between Windows workstation(from where upgrade is performed) and vCenter on firewall.
It is required for Windows workstation to access vCenter VAMI page (port 5480) to proceed to stage two of upgrade.

Resolution

Unblock port 5480 between Windows workstation and vCenter on firewall.