Uma configuração antiga de um agente do vcenter ainda deve estar lá no esxi, pois, por favor, veja o fato lá: Portas necessárias para o VMware vCenter Server 5.5 (2051575)
902
TCP/UDP
This is the default port used by the vCenter Server system to send data to managed hosts. Managed hosts also send a regular heartbeat over UDP port 902 to the vCenter Server system. This port must not be blocked by firewalls between the server and the hosts or between hosts.
Por favor, siga essa KB para remover qualquer traço do Vcenter: Desinstalando o vpxa no ESXi (1005482)
Para desinstalar o agente vpxa:
1.From the main yellow and gray screen on the ESXi host, press Alt-F1.
2.At the next screen, type:
unsupported
3.When prompted, enter the root password.
4.Execute the following command:
/opt/vmware/uninstallers/VMware-vpxa-uninstall.sh
Note: The vpxa agent automatically re-installs once the ESXi host is connected to vCenter Server.