Error: "Could not connect to one or more vCenter Server Systems" in the vSphere Client

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• The VMware vSphere Client displays the below error:
  Failed to verify the SSL certificate for one or more vCenter Server Systems: https://<vCenter-FQDN-Or-IP>:443/sdk
  Could not connect to one or more vCenter Server Systems: https://<vCenter-FQDN-Or-IP>:443/sdk
   
• Objects such as host or virtual machines are not displayed in the vSphere Web Client

• Using lsdoctor Using the 'lsdoctor' Tool run check command use - 'python lsdoctor -l' the result display's duplicate endpoints.
  
  YYYY-MM-DDTHH:MM:SS ERROR generateReport: <site>\<vCenter_FQDN> (VC 7.0 or CGW) found Duplicates Found: Ignore if this is the PSC HA VIP.  Otherwise, you must unregister the extra endpoints.

Environment

• VMware vCenter Server 7.0
• VMware vCenter Server 8.0

Cause

This issue occurs in these situations when using Enhanced Linked Mode:

• Another vCenter Server in the Single Sign-On (SSO) domain has restarted or is not fully available after restart.
• During the re-installation of the vCenter Server, it is possible to have the same vCenter Server registered more than once to the Single Sign-On (SSO).
• With a previous install of vCenter Server, SSL certificates were not overwritten or appropriately removed during an upgrade or re-installation.

From the logs /opt/vmware/hms/logs/hms.log, shows registration already exists .

-- > vSphere Replication Appliance configuration error:vCenter Server extension configuration problem.
-- > Details: Unable to register extension in vCenter Server.
-> [ msgId: com. vmware. vr.config. ext_config_failure; value: null; errorStacktrace : com. vmware. jvsl.cfg. ConfigException: Internal error.
at com. vmware. jvsl.cfg.RegisterExtensionCommand.execute(RegisterExtensionCommand. java: 154)
at com. vmware.hms.config.helper. VcHelper. registerExtension( VcHelper. java:280)
at com.vmware.hms.config. VrConfig.expressSetup(VrConfig.java:358)
at com.vmware.hms.config.cli.command.ExpressSetup.run(ExpressSetup.java:59)
at com. vmware.hms.config.cli.command. CommandBase.run(CommandBase.java:347)
at com. vmware.hms.config.cli.App.run(App.java:146)
at com. vmware.hms.config.cli.App.main(App.java:206)
-- > Caused by: (vim. fault.AlreadyExists) {
faultCause = null,
faultMessage = null,
name = null

Resolution

Important: Kindly raise a support ticket via the, Broadcom Support Portal to safely proceed with below solution steps.

Note:

• Capture offline snapshots for vCenters in linked mode.
• This issue may be transient as another vCenter Server in an Enhanced Link Mode domain is restarting. Before continuing with troubleshooting, it is advised to wait 10 minutes, log out, and log back into the vCenter Server. The error may clear on its own. In addition, it is strongly advised to determine if logging into the other vCenter Server identified in the error message directly to determine if vCenter services are up and running before continuing. If all vCenter Servers are up and running and this error persists, continue with this resolution to identify duplicate service registrations or other errors.

To resolve this with scripting, refer to below articles:

Using the VCF Diagnostic Tool for vSphere (VDT)

Using the 'lsdoctor' Tool