I was working on a migration to get rid of a vCenter/PSC running on a Windows server. So I started the VMware Migration Assistant on the PSC that I wanted to migrate. Then I started the vCenter Server Appliance Installer on a different Windows server and filled in the configuration details like VM name, temporary IP address and the name of the vCenter Server etc.

Everything was fine and the tool started the deployment of the appliance. But after a couple of seconds I got an error: failed to send HTTP data.

The log file didn’t give me any specific reason why the deployment failed. But PortQry did!

The system on which you are running the Installer must have access to the source system on port 9123 and access to vCenter AND the ESXi hosts on port 443.