Unable to connect to vCenter appliance management page on port 5480 "This site can't be reached <vCenter FQDN/IP> refused to connect"

Products

• VMware vCenter Server

Issue/Introduction

• Connection to vCenter UI works as expected.
• Following error is observed on web browser : 
  This site can't be reached  <vCenter FQDN or IP> refused to connect.  Try: . Checking the connection . Checking the proxy and the firewall .
  
  
•  Following logs are observed in journalctl.log. This can validated by running following command: 

     journalctl -r | grep lighttpd

     MM DD HH:MM:SS  < vCenter FQDN or IP> kernel: vami-lighttpd[26125] : segfault at 0 ip 00000000004272de sp 00007ffd3df15450                 error 4 in vami-li  ghttpd[400000+3a000]
     MM DD HH:MM:SS8 < vCenter FQDN or IP> audit [26125] : ANOM_ABEND auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined               pid=26125 comm="vami-lighttpd" exe="/opt/vmware/sbin/vami-lighttpd" sig=11 res=1           

•  /opt/vmware/var/log/lighttpd/error.log gives following snippets:
   YY-MM-DD HH:MM:SS: (/build/mts/release/bora-16973022/studio/src/vami/apps/lighttpd/src/connections-glue. c. 200) SSL: 1 error:       140760FC: SSL routines: SSL23_GET_CLIENT_HELLO: unknown protocol
 YY-MM-DD HH:MM:SS: (/build/mts/release/bora-16973022/studio/src/vami/apps/lighttpd/src/connections-glue. c. 200) SSL: 1 error:       140760FC: SSL routines: SSL23_GET_CLIENT_HELLO: unknown protocol

• Checking for the port 5480, we find that this port is in not listening state. Running the following command gives a blank output.
  netstat -anop | grep 5480 

•  Checking  the status of vami-lighttp service is good but will error out in the logs. Status of the service can be checekd by running following command.
  systemctl status vami-lighttp.service

Environment

vCenter 7.x
vCenter 8.x

Resolution

To fix this this issue, restart the lightttp service using the following commands.
systemctl stop vami-lighttp.service
systemctl start vami-lighttp.service