Diagnostics for VMware Cloud Foundation: Ensuring Availability of vCenter: Troubleshooting Guide
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Diagnostics for VMware Cloud Foundation: Ensuring Availability of vCenter: Troubleshooting Guide

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Article ID: 381705

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Updated On:

Products

VCF Operations

Issue/Introduction

vCenter is the centralized management component for ESXi hosts and is critical for the operation of your VCF environment. When monitoring vCenter, most administrators focus on the VM's status and its ability to respond to a ping. While these are essential checks, they do not provide a complete picture of vCenter's health and accessibility.

A VM can be up and pingable, yet:

  • Network issues can prevent access to vCenter.
  • The UI may be inaccessible even though core vCenter services appear to be running.
  • API integrations might fail due to excessive connections, exhausting the vCenter API session limit of 2000 sessions.

To address these gaps, VCF Health enhances monitoring by assessing vCenter connectivity across three key parameters:

  1. Ping: Checks whether vCenter VM is running and is accessible
  2. UI: Verifies accessibility and functionality of the vCenter user interface.
  3. API: Confirms that integrations using vmodl1 APIs are functioning correctly without session overload.

These checks are performed every 5 minutes. 

Environment

Operations for VMware Cloud Foundation 9.0

Resolution

Ping Check Failure

When the Ping Check fails, it indicates potential issues with VM availability, ESX host connectivity, or network configuration. Follow these steps to diagnose and resolve the issue:

  1. Test Connectivity:
    • Ping the vCenter from a device in the same subnet it is running on, and from another subnet.
    • If you can ping from the same subnet but not across subnets, the issue likely lies with the network or firewall configuration.
  2. Verify vCenter Power Status:
    • If ping fails across all subnets, check if the vCenter VM is powered on.
  3. Locate the vCenter VM:
    • When vCenter is not pingable, it could be running on a network isolated host or could not have been restarted by vSphere HA, if HA was enabled. 
    • Use VCF Operations to determine the last host on which the VM was running
    • From the Connectivity Page in VCF Health, click on the vCenter name to navigate to the vCenter Summary.
    • Open the Topology View to find the vCenter VM.
    • Click on the vCenter VM to view its VM Summary, which shows the ESX host on which it is running. The host on which the vCenter is running is updated every five minutes when VC is accessible from VCF Operations.
    • To determine the path to the configuration file of the VM, navigate to the property list of the VM and open the summary property group. The vSphere moID is given. Switch to the log tab and search the cluster logs for the moID. If logs were collected from the cluster, there will be log statements that list the vmx path.
  4. Check ESX Host Status:
    • Attempt to log in to the ESX Host Client of the host determined in step 3
    • If you can log in and vCenter is not running, you can try registering it and powering it on. Use the path determined in step 3 to register the VM. 
    • If you are unable to connect to this host or you cannot power on vCenter because its disks are locked, log into the other hosts in the cluster to locate the VC VM.

UI Check Failure

A UI Check failure indicates that vCenter services may not be running or access to the interface is blocked. Resolve the issue with the following steps:

  1. Verify Services:
    • Navigate to the Services Section 
    • Ensure that all critical services are running.
  2. Check Firewall Settings:
    • If services are running but the UI remains inaccessible, inspect the firewall configuration for rules that may block UI access.

API Check Failure

An API Check failure suggests issues with firewall settings or API session limits. Use these steps to troubleshoot:

  1. Firewall Configuration:
    • Confirm that the firewall is not blocking the API ports.
  2. API Session Limit:
    • Check if the vCenter has reached its API session limit, and if necessary, adjust the session settings to accommodate integration requirements.

 

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