Getting a 503 error when trying to access the HTML5 vcenter client

Hello, I have taken over management of a small vsphere cluster of three hosts managed by a vcenter VM on host1. Since I started I have not been able to access the HTML5 web interface. The flex client works but requires flash and is deprecated. VCenter and the hosts are all on the newest version of 6.7. I have searched for a solution for weeks but cannot seem to resolve this issue. Error is below thanks in advance.


When I click on HTML5 client button I am redirected to a white page that only displays the following..

“503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x00007f7d80117c50] _serverNamespace = /ui action = Allow _port = 8080)”

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  1. Firewall? I assume you’ve read the KBs regarding this message.

    Can you sign into the appliance directly? Any events/errors?

    If you have support, open a ticket.

  2. Check DNS, if your DNS is not reachable, check that the address on the vcsa console and etc hosts file on vcsa match the up and be sure at is only configured for localhost not the real hostname.

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