Connecting to the ESXi UI fails after upgrade.

Products

• VMware vSphere ESXi 7.0
• VMware vSphere ESXi 8.0

Issue/Introduction

Connecting to the ESXi UI  fails after upgrade :

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

Environment

rhttpproxy.log

2025-03-23T08:28:40.351Z verbose rhttpproxy[2101047] [Originator@6876 sub=IO.Connection] Attempting connection; <resolver p:0x
000000f224407e30, 'localhost:8309', next:<TCP '127.0.0.1 : 8309'>>, last e: 0(Success)
2025-03-23T08:28:40.351Z warning rhttpproxy[2101050] [Originator@6876 sub=IO.Connection] Failed to connect; <io_obj p:0x000000
f266d03e68, h:18, <TCP '127.0.0.1 : 57707'>, <TCP '127.0.0.1 : 8309'>>, e: 111(Connection refused), duration: 0msec
2025-03-23T08:28:40.351Z info rhttpproxy[2101050] [Originator@6876 sub=IO.Connection] Failed to shutdown socket; <io_obj p:0x0
00000f266d03e68, h:18, <TCP '127.0.0.1 : 57707'>, <TCP '127.0.0.1 : 8309'>>, e: 104(shutdown: Connection reset by peer)
2025-03-23T08:28:40.351Z verbose rhttpproxy[2101050] [Originator@6876 sub=IO.Connection] Attempting connection; <resolver p:0x000000f224407e30, 'localhost:8309', next:(null)>, last e: 111(Connection refused)
2025-03-23T08:28:40.351Z warning rhttpproxy[2101050] [Originator@6876 sub=Proxy Req 00085] Connection to localhost:8309 (/) failed with error N7Vmacore15SystemExceptionE(Connection refused: The remote service is not running, OR is overloaded, OR a firewall is rejecting connections.)

Cause

This type of issue can occur due to port blocking at Firewall level or due to additional lines in endpoints.conf file.

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 #.#.#.# allow allow
=============

After changes, endpoints.conf file should look like:

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