Skip to main content
Contact Us
Some article numbers may have changed. If this isn't what you're looking for, try searching all articles. Search articles

VMware: How to Troubleshoot vSphere HA if it Does Not Enable or Fault domain manager Agent Does Not Install on the ESXi Hosts

Summary: This article explains requirements for enabling vSphere HA in a VMware Cluster and resolving issues with Fault domain manager (FDM) agent installation on ESXi hosts.

This article applies to This article does not apply to This article is not tied to any specific product. Not all product versions are identified in this article.
Check out other resources

Instructions

Troubleshoot issues when enabling vSphere HA in a vSphere Cluster or when Fault domain manager (FDM) Agent does not install on the ESXi hosts.

Facts:
vSphere HA
vSphere Clusters
Fault domain manager (FDM) Agent.

Procedure:

  • If vSphere HA does not enable, take the following steps:
  1. Disable and reenable or reconfigure vSphere HA on the cluster. This check resolves most issues.
  2. Check the release notes for known issues with vSphere HA and verify that vSphere is on the latest version.  
  3. Check the Fault domain manager (FDM) logs that are on the ESXi hosts and search for error messages.

Logs to review on the ESXi host to identify the cause of the issue. 

  • FDM Operations log: /var/log/fdm.log or /var/run/log/fdm
  • FDM agent Installation log: /var/log/fdm-installer.log

Possible causes of this issue

  • vSphere HA is not properly configured.
  • The datastore for vSphere HA heartbeats is not accessible by all hosts.
  • The FDM agent is not installed properly on the ESXi host.
  • The network connectivity is lost between the ESXi host and the vCenter Server.
  • The ESXi host is not properly connected to vCenter Server.

 

  • FDM agent does not install on the ESXi host.

If the FDM agent cannot be installed on the ESXi host, do the following checks:

  1. Check the FDM log for errors: /var/log/fdm.log
  2. Verify that sufficient network bandwidth exists between the ESXi host and vCenter Server.
  3. Check for a hardware issue if network traffic throughput is causing the issue.
  4. Check that disk space is available on the ESXi host in /var and /tmp. Use the command:
vdf -h 


​​​​​​If the issue for the install of FDM Agent on the ESXi host is related to network traffic, identify what the cause of the issue is:

  • Hardware issue with the Network Interface Controller (NIC)
  • Mismatch between NIC speed and switch speed
  • Hardware or firewall is blocking or slowing traffic.

Also, verify that the FDM agent files were pushed from vCenter to the ESXi host by checking that the following files exist on the ESXi host in the /etc/opt/vmware/fdm directory:

  • Cluster configuration: Clusterconfig
  • FDM configuration file: fdm.cfg
  • Host membership list: Hostlist
  • List of all Virtual Machines (VM) and the hosts that they are compatible with: Vmmetadata
See the example screenshot below:

Verify files were pushed from vCenter to the ESXi host
Figure 1: Verify that files were pushed from vCenter to the ESXi host.

Additional Information

Related VMware Articles:

Affected Products

PowerFlex rack, ScaleIO, PowerEdge FC640, PowerEdge M640, PowerEdge M640 (for PE VRTX), PowerEdge MX740C, PowerEdge MX750c, PowerEdge MX760c, PowerEdge MX840C, PowerEdge R240, PowerEdge R250, PowerEdge R260, PowerEdge R340, PowerEdge R350 , PowerEdge R360, PowerEdge R440, PowerEdge R450, PowerEdge R470, PowerEdge R540, PowerEdge R550, PowerEdge R640, PowerEdge R6415, PowerEdge R650, PowerEdge R650xs, PowerEdge R6515, PowerEdge R6525, PowerEdge R660, PowerEdge R660xs, PowerEdge R6615, PowerEdge R6625, PowerEdge R670, PowerEdge R740, PowerEdge R740XD, PowerEdge R740XD2, PowerEdge R7415, PowerEdge R7425, PowerEdge R750, PowerEdge R750XA, PowerEdge R750xs, PowerEdge R7515, PowerEdge R7525, PowerEdge R760, PowerEdge R760XA, PowerEdge R760xd2, PowerEdge R760xs, PowerEdge R7615, PowerEdge R7625, PowerEdge R770, PowerEdge R7715, PowerEdge R7725, PowerEdge R840, PowerEdge R860, PowerEdge R940, PowerEdge R940xa, PowerEdge R960, PowerEdge T140, PowerEdge T150, PowerEdge T160, PowerEdge T340, PowerEdge T350, PowerEdge T360, PowerEdge T40, PowerEdge T440, PowerEdge T550, PowerEdge T560, PowerEdge T640, VMware ESXi 7.x, VMware ESXi 8.x, VxBlock and vBlock Systems Series ...
Article Properties
Article Number: 000207170
Article Type: How To
Last Modified: 09 May 2025
Version:  5
Find answers to your questions from other Dell users
Support Services
Check if your device is covered by Support Services.