ISSUE:

Connecting to the ESXi Web interface (https://esxi/ui) fails.
You see entries as below to:

503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x04d36508] _serverNamespace = / action = Allow _port = 8309)

OBSERVATION:

— When we check the file /etc/vmware/rhttpproxy/endpoints.conf found that there few additional lines added (below Snippet from my lab) which was causing this issue.

error

RESOLUTION:

Take a backup of endpoints.conf file

Delete below line from /etc/vmware/rhttpproxy/endpoints.conf file and restart ESXi host management services.

=============
/ remote 10.170.2.2.3128 allow allow
=============

After changes, endpoints.conf file should look like:

After

Now we should be able to login, on the ESXi host web interface.