Disconnect hosts from vCenter via database when vCenter fails to start

Products

• VMware vCenter Server

Issue/Introduction

vCenter continually crashes while trying to start.

Environment

VMware vCenter Server 6.x

VMware vCenter Server 7.x

VMware vCenter Server 8.x

Cause

vCenter is stopping due to issues at the host level.

Resolution

To narrow down which host is causing the issue you can disconnect all hosts from the database and then add them back one by one until you locate the culprit for closer inspection.

• Please make sure vCenter is stopped, if required set the service startup type to "Manual" and Take a backup of the vCenter database first.
  • https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/8-0/vcenter-server-installation-and-setup-8-0.html
  • To disconnect all hosts connected to vCenter:
    • /opt/vmware/vpostgres/current/bin/psql -d VCDB -U postgres -c "UPDATE vpx_host SET enabled=0"
  • Validate the changes by running the below command.  
    • /opt/vmware/vpostgres/current/bin/psql -U postgres -d VCDB -xc "select * from vpx_host;" | grep "enabled "
      
      
• If you wish to narrow this down you can use the command below instead to disconnect only a single host:
  • /opt/vmware/vpostgres/current/bin/psql -U postgres -d VCDB -xc "select * from vpx_host;"  |egrep "id |dns_name |enabled "
  • /opt/vmware/vpostgres/current/bin/psql -d VCDB -U postgres -c "UPDATE vpx_host SET enabled = 0 where id = <host-id>;"
    
    
• Script to connect all hosts including 30 second wait between connects. Copy it to file and run from the same location as powercli (desktop)
  • Open powershell
  • Run: Connect-VIServer -Server EXAMPLE_FQDN/IP_OF_VCENTER
  • To run the script, use the following syntax with the file name you chose:

./<filename>.ps1

 

-----------------------------------

$password = "EXAMPLE_PASSWORD"

get-vmhost | % {
$view = get-view $_.id
$arg = new-object VMware.Vim.HostConnectSpec
$arg.userName = "root"
$arg.password = $password
$arg.force = $true

$view.ReconnectHost_Task($arg,$null)
}

Disconnect-VIServer -Confirm:$false

--------------------------------------

 

Note that : EXAMPLE_PASSWORD = your custom ESXi password

 

Notes:

• This will only connect ESXi hosts with the same password.
• You probably will need to answer the certificate question regarding the thumbprint. Accept this if it appears.