"No Healthy Upstream" when accessing vCenter UI thru the web browser.

Products

• VMware vCenter Server

Issue/Introduction

When accessing vCenter UI in the web browser getting "No Healthy Upstream"

Getting following errors in the logs:
vapi-endpoint service won't start with the below errors

/var/log/vmware/vapi/endpoint/endpoint.log
YYYY-MM-DDTHH:MM:SS | ERROR | state-manager1            | DefaultStateManager            | Unexpected error while initializing endpoint runtime state.
com.vmware.vim.sso.admin.exception.InternalError: General failure.

/var/log/vmware/sso/tomcat/catalina.log:

Unable to load server configuration from /usr/lib/vmware-sso/vmware-sts/conf/server.xml 

All certificates show valid including STS.

Environment

vCenter 8.0.x

Cause

Issue with server.xml file reported in /var/log/vmware/sso/tomcat/catalina.log 

Resolution

Deploy or find working vCenter with the same build number.

Take the contents of /usr/lib/vmware-sso/vmware-sts/conf/server.xml and update the /usr/lib/vmware-sso/vmware-sts/conf/server.xml on the broken vCenter.

Restart services: service-control --stop --all && service-control --start --all